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January 27

SHA1 checksum for Firefox 44.0

I downloaded and installed the US English version of Firefox from firefox.com but it came with all sorts of non-English and suspicious looking addons. I doubled-checked the HTTPS connection to firefox.com and that its certificate is genuine, as far as I can tell. https://download.mozilla.org/?product=firefox-44.0-SSL&os=win64&lang=en-US[1] was the exact download link I used.

Does Mozilla publish SHA1 checksum for their Firefox binaries so that I can verify what I downloaded was genuine or not? Johnson&Johnson&Son (talk) 06:26, 27 January 2016 (UTC)

For reference, what I downloaded[[2]] has a SHA1 hash of a6f058b8fd8430db0f87746c331877e7f3c40078. Johnson&Johnson&Son (talk) 06:29, 27 January 2016 (UTC)

I managed to find this link[3], but it's a little outdated. The example http://releases.mozilla.org/pub/mozilla.org/firefox/releases/3.6.13/ still works, but unfortunately http://releases.mozilla.org/pub/mozilla.org/firefox/releases/4.40 doesn't work. Johnson&Johnson&Son (talk) 10:49, 27 January 2016 (UTC)

If you already had Firefox installed, bear in mind installing a new version isn't generally going to remove addons. If you had it installed at some stage but uninstalled it, the addons may still hang around. If you never had Firefox installed, it's still possible other software may have set themselves to be added to Firefox if you even installed it. Particularly malware.

Browsing this directory [4], you should be able to find the hashes that Mozilla published for your release. For 44.0 (not 4.40 which never existed) the SHA2-512 hashes are here [5] and it's c4ef058366ae0e04de87469c420761969ee56a03d02392a0cc72e3ced0f21be10e040750f02be3a92b6f25e5e2abdc30180169ae2bc84ef85c5343fdf9b632cf.

There are no MD5 or SHA1 hashes, I presume Mozilla stopped publishing them a while ago considering neither are considered secure. However unlike MD5, the cost of generating a SHA1 collision (particularly a useful SHA1 collision) is as far as we know, high enough that I think it's fairly unlikely that you happened to have a version with the same SHA2-512 hash but a different SHA1. And I can confirm that the file I just downloaded has the same SHA2-512 as I see published my Mozilla and SHA1 that you published. [6] also has the same SHA1.

Note however I did not verify the hash file I downloaded using the GnuPG [7] which means if my connection was also compromised, my hashes are useless. Note also if you do have malware, any hash you generate, any certificate that appears genuine, any verification of the hash file is basically useless. (And even if you went through this much effort fo all the software you ever downloaded and ran on your computer, the existing of bugs means it's still impossible to be certain you don't have malware.)

However most malware doesn't go that far. In fact, I can only imagine the certificates ever really happens unless you were particularly targetted e.g. by a very dedicated and smart individual, or a criminal group or an intelligence agency, who for some reason are out to get you. Of course if this is happening, you may not be reading my message (either at all or in original form) either so....

Presuming you're correct about weird addons, personally I think the most likely thing is your system was already somewhat compromised but the software you just downloaded is the genuine original file.

Nil Einne (talk) 13:18, 27 January 2016 (UTC)

Thanks. Seems like it's indeed the add-ons from a previous "dirty" installation of Firefox that's causing the problem. I tried uninstalling firefox, restarting, and installing it again but all the add-ons from the previous version is still there. How do I prevent this from happening? I want to completely wipe everything Firefox related, and then install from one of the SHA512 verified binaries. I'm on Windows 10. Johnson&Johnson&Son (talk) 04:37, 28 January 2016 (UTC)

I would try a Firefox "refresh". Uninstalling Firefox does nothing because it doesn't touch your profile, which is where extensions, settings, and the like usually live. Uninstalling simply removes the program files. --71.119.131.184 (talk) 05:06, 28 January 2016 (UTC)

Also, if you haven't you should scan your computer with some anti-malware software. Microsoft's Malicious Software Removal Tool is a good place to start. Maybe also try MalwareBytes and Spybot – Search & Destroy. And ensure you are running antivirus and anti-malware software. Microsoft Security Essentials is free to anyone with a registered copy of Windows, and it seems to be good enough, although there are plenty of other choices. --71.119.131.184 (talk) 05:17, 28 January 2016 (UTC)

YES! Thank you so much! The refresh was exactly what I needed. Much appreciated! Johnson&Johnson&Son (talk) 05:42, 28 January 2016 (UTC)

BrowserFox is one of the malwares I had on my home computer recently, and it would persist addons across new browser installs (notably "OutrageousDeals!" adware). It may be worth it to run a malware scan using your favorite application and see if it picks up anything. FrameDrag (talk) 14:36, 27 January 2016 (UTC)

Windows Batch File Repair

I've Googled how to repair Windows Batch Files and can only find how-tos on repairing Windows with batch files.

How do I repair an improperly working Batch File containing a game?? Theskinnytypist (talk) 18:56, 27 January 2016 (UTC)

Just open it in a text editor (not a word processor that adds unwanted characters) and edit it, then re-save. Dbfirs 19:32, 27 January 2016 (UTC)

A batch file is a batch of commands. Batch files execute the commads listes in it. NOTEPAD.EXE – also called "Editor" comes with Windows. It allows You to view and edit batch files. Later versions of DOS came with EDIT.EXE. --Hans Haase (有问题吗) 12:26, 28 January 2016 (UTC)

A "repair" is You to get the original file or reprogramm it Yourself. Careful, You are dealing with executable commands that can make changes to Your computer! --Hans Haase (有问题吗) 12:28, 28 January 2016 (UTC)

If the batch file was "damaged" (ie the contents were changed somehow) - and you didn't actively change it - then the odds are good that it's totally corrupt. Even if the damage is just a few characters - unless you know a lot about batch files (and you clearly don't) - AND a lot about how your game needs to be launched (tough for anyone to figure out) - then I very much doubt you'll be able to repair it with a text editor. Not because it can't be done - it certainly can - but because you need so much other knowledge that you don't have - and may not even be able to get. So in all probability, you'll have to re-install that file from wherever you got the game - which probably means you'll have to re-install the game itself. SteveBaker (talk) 14:59, 28 January 2016 (UTC)

Finding where in my computer an open document is located

When I'm in finder and highlight some document, say after a search, I know where exactly it's located in my computer because it tells me at the bottom of the finder window. I can also click Command+I and that will also tell me its saved location. However, if I have a document open, say a Word document, and want to be told where that document is saved in my computer, how do I do that? (*Command+I" in an open document just invokes italics). I know of indirect ways. For example, I could copy and paste some unique text from it and do a search, but I was thinking there must be some easier and more direct way. Thank you.--108.21.87.129 (talk) 18:58, 27 January 2016 (UTC)

In most applications, including Microsoft Office, you can just click "save as" and it will show the current saved location as the default. Dbfirs 19:38, 27 January 2016 (UTC)

(ec) It probably depends on version, but in Word Starter 2010, just click on File, and you will see the document location under "Information about <file name>". Rojomoke (talk) 19:43, 27 January 2016 (UTC)

Ah, I've figured it out. Save as is not reliable. In excel for example it always tries to save in the last location where you saved any excel file, and not the location where the file you have open is from (a terrible feature). But the answer is that, while I don't have the facility Rojomoke describes, I can click on properties from the file menu tab, and in there click on the general tab where the location is set out.--108.21.87.129 (talk) 20:51, 27 January 2016 (UTC)

My older version of Excel does that only for a regular save, but I'm glad you've found a solution. Dbfirs 21:24, 27 January 2016 (UTC)

On OS X, you can Command+Click the document icon on most NSWindows. (It's the little icon, usually immediately to the left of the file name, in the window's Title Bar). This will show you the file system representation for the document that is open. You can also drag-and-drop the document icon onto Terminal or a text-editor, and it will emplace the pathname of the document in the terminal.

Most applications, including Microsoft Word for OS X, provide this "smart" document icon feature.

Once the UI springs up, you can select the parent folder and immediately open a Finder window there. Or, you can drag the icon from the open window's title bar onto a dock icon for a different application (if that application knows how to open the file type).

I can't seem to recall the name for this amazing UI feature; but here is technical documentation about how it works: NSWindow setTitleWithRepresentedFilename: (and window:shouldPopUpDocumentPathMenu:).

I want to say that the common name for this feature is the "active document icon" or "smart document icon" or something to that effect. If you play with the feature, it can do all kinds of other useful things related to drag-and-drop.

Nimur (talk) 00:04, 28 January 2016 (UTC)

Thanks! That is a very satisfactory answer to a question I had for a long time! --Stephan Schulz (talk) 13:58, 28 January 2016 (UTC)

Another option: type the file name you want (or text from it) into Spotlight, then when you have the one you want selected hit Cmd+R. Blythwood (talk) 21:58, 29 January 2016 (UTC)

January 28

Mouse Cursor Jumping Around

I edit Wikipedia using either of two computers, a desktop computer running Windows 7, and a laptop computer that is now running Windows 10, both using a mouse. (I don't plan to learn to use a trackpad.) On the laptop, I frequently have a problem with the mouse cursor jumping around, moving to where I don't want it. If I notice this before typing, I can move it back, and may have to undo the selection that it did while moving. If I don't notice until I type, I then realize that a considerable amount of text (that had been highlighted by the moving around) may have disappeared, or just that I have typed in the wrong place. This requires Ctrl-Z. No permanent harm done, but a nuisance. This never happens with the desktop machine. I have two possible theories as to the cause, and will listen to another. First, on the desktop, I have the mouse sitting on a brown wooden computer desk, but on the desktop, the mouse may be sitting on a white tablecloth or a white piece of paper or a magazine. Does the issue have to do with the surface, in which case would buying a small mouse pad help with the laptop? Alternatively, is the problem due to a bug or a setting in Windows 10? I knew that Windows 8, before upgrading to Windows 8.1, sometimes had mouse jump. Is there a mouse jump bug or misfeature in Windows 10? If so, this will cause me to choose not to upgrade from Windows 7 (which works fine for me) to Windows 10. Which is a more likely explanation? Is there a third explanation? Robert McClenon (talk) 00:13, 28 January 2016 (UTC) By the way, this also happens in Word. It isn't a Wikipedia thing in particular. It's a mouse thing. Robert McClenon (talk) 00:14, 28 January 2016 (UTC)

On the laptop you have a track pad that you don't use, is that right? Try actually disabling the track pad, you should be able to do this somewhere under device manager. I have seen this issue caused by track pad bugs. Vespine (talk) 04:59, 28 January 2016 (UTC)

Generally not so much a bug, as just the user's palm hitting the trackpad and causing an extra input. MChesterMC (talk) 09:26, 28 January 2016 (UTC)

Similar effects are caused by defect or wet optical mouse or placing it on shining surfaces like glas. --Hans Haase (有问题吗) 12:50, 28 January 2016 (UTC)

The optical mouse actually uses a small camera to look at the desktop with an LED light to illuminate it. It looks for movement in the image it sees but if the surface is very shiney, or transparent or if it's very uniform in brightness, it won't be able to measure motion accurately. Something like a page full of text in a magazine should work really well - so if you try that and the symptoms go away, then you might want to invest in a mouse-pad. I agree with the previous suggestion to disable the trackpad - that could be producing spurious results. If neither of those things work, then I'd try swapping the mouse (and the little USB gizmo if it's wireless) between the two machines and seeing if the problem stays with the laptop or becomes a problem on the desktop machine. If the fault follows the mouse then you might try changing the battery (if it's wireless) - and perhaps cleaning the lens underneath the mouse. Another possibility is that you somehow changed the mouse settings to give it crazy high speed or acceleration sensitivity. Find the mouse setup stuff in the control panel and set it back to the default settings. One weird mouse fault I once had was due to that camera under the mouse having a very specific focal length lens on it - so almost any variation in the height of the camera over the desktop would cause it to fail. The mouse had somehow lost it's little rubber feet - which lowered it a millimeter or two putting the camera out of focus...that's a long-shot though! SteveBaker (talk) 14:55, 28 January 2016 (UTC)

Clarifying that a magazine only works well if it's not glossy (as many are). A newspaper or any text on matte paper should be an ideal test that can rule out surface issues (or suggest that they are the problem). Real wood is also a pretty great optical mousing surface, though my cheap glossed laminate top does cause some slight skipping compared to better surfaces. Speaking of which, the people who really care about optical mouse response and control sensitivity are gamers, so OP might peruse these mouse pads if he decides on that route [8] SemanticMantis (talk) 17:01, 28 January 2016 (UTC)

Laserjet printer

Dear Sir

I purchased second hand an Epson Aculaser c2900 color laserjet printer.

It has full blue, red, and yellow ink cartridges, however the black is empty. I am wondering if this printer will continue to print the color black text even with an empty black cartridge by mixing the blue, red, and yellow inks together to make black. Will this printer do this?

I read on the manufacturer website that it says "auto-switching to monochrome printing when color toners are depleted" which is the reverse of what I am asking. However the issue of empty black cartridge is not addressed.

Please let me know here, I am forbidden from giving you my email. — Preceding unsigned comment added by 122.15.163.132 (talk) 00:55, 28 January 2016 (UTC)

I don't really have a reference but I'm fairly certain most printers can not print black by using the color cartridges. While no doubt it would be "technically" possible to achieve this, I believe most printers require at least the black to print anything. Vespine (talk) 02:50, 28 January 2016 (UTC)

I doubt it will. The auto switch to monochrome is the opposite - print in B&W if the color ink is out. Bubba73 ^{You talkin' to me?} 04:39, 28 January 2016 (UTC)

Never operate a machine without toner. Toner is also a dry lubricant for the photo conductor. A damage of the photo conductor has an negative impact to the print quality and toner consumption. It also may affect the fusing unit whithin al larger number of prints. Do not operate a machine using cartridges containing toner only. When toner and photo conductor drum are separate units, the specific toner might be a two component toner which is not including the magnetic matieral. Single component toner is magnetic. New two component toner is not magentic. Blended two component toner behaves also magnetic. When operating a machine with empty the two component toner, the magnetic carrier material will be pulled to the photoconector and scrape it. This will not happen when the high voltage is operating normal and theres enough toner in the unit. The EPSON C2900 has toner only cardridges. Refill kits with chip replacement are avail.[9] It might have two component toner and a chip replacement was done. Check the instuctions what to do when refilling the toner. A mix of original and refilled toner migh have a impact on the print quality. --Hans Haase (有问题吗) 12:18, 28 January 2016 (UTC)

Note that even if it would do so, it's not a good idea. The mixed color black won't look very black, and you will use up the more expensive color toner. StuRat (talk) 03:44, 29 January 2016 (UTC)

How do you make a software to store huge quantities of information on your computer?

troll
The following discussion has been closed. Please do not modify it.
Let's say you want to make a game. Many games allow people to save game and load old game. How do you make save and load? I've noticed that some games save game information in their own file format. How do people make their own file format? 140.254.136.157 (talk) 18:15, 28 January 2016 (UTC) Complex file formats might be a container file format for several information. Typical specialized files formats contain just a header which describes the following content. Simple files, like plain text begin the content with the first byte. To access a huge number of data records, a data record of a table is being defined. This are relational databases. When data does not fit into records or ohter information is beeing taken from, see NoSQL. This are the chats and postings of social networks for exaple. --Hans Haase (有问题吗) 18:42, 28 January 2016 (UTC) I have the impression that games would rather save in an xml format/text format and use an own extension like mygamedata.mygame. That's the easy way. You could also create a custom binary file.--Scicurious (talk) 20:53, 28 January 2016 (UTC) It's all bytes. Many video games use game engines and/or software libraries that may make things easier for the programmer(s), but ultimately, you write bytes to a file, and read them back. Nothing personal, but this is a fairly basic programming question, so if you want a comprehensive answer you should probably start diving into learning how to program. Writing a simple video game is a good project for learning. --71.119.131.184 (talk) 02:34, 29 January 2016 (UTC) I'm guessing from your Q that you imagine it saving all the images you see in every scene of the game. It's not done like that. Let's imagine a monster shoot-em-up where a vampire with 27% of his strength left is in room E8, that could be saved in a file as something like "E8VA27", or even less if you didn't care about making the file human readable. StuRat (talk) 03:41, 29 January 2016 (UTC) A lot depends on whether the game allows you to save at literally any point - or only as specific points in the game (such as passing into a new level). In the latter case, you may only need to store the number of the level the player just reached, and their score/health/ammo/inventory. This may be a very small amount of information...a couple of dozen bytes maybe. But if you can save literally anywhere - then the player's position, speed, direction - along with that of all of the enemies - and maybe things like the current mental state of the AI's in the game and the amount of destruction done to the environment - which collectable items are now 'consumed'. So this can wind up being a much more complex problem. It's not at all unusual for programmers to forget to save every last scrap of important information (especially where things are randomly generated) - and it can sometimes be noticeable that when you 'restore' the game, everything isn't precisely as it was when you saved it. But (as StuRat points out) - what's being saved isn't pictures of the action or anything like that. Actual file formats vary tremendously. While it's easier for the game to save and load a convenient format like XML, there is a problem with players cheating by hand-editing the file to give themselves more lives or a higher score or something...and that's generally considered highly undesirable. So quite often the file format will be obfuscated and quite possibly encrypted in order to make life harder for cheaters. The amount of saved information is generally very small - hundreds to thousands of bytes in most cases. But there are exceptions. In games where the environment is heavily modified by the player (think of something like SimCity - where the entire city is created by the player as the game progresses), there might be a more significant amount of data to save in order to preserve every detail of the current game state. Making your own file format is very easy - whatever data you choose to write into the file is your choice - and when you do that, you effectively have "your own file format". It's actually rarer to NOT have your own file format because in order to make something standard that encapsulates some special aspects of your game is harder. But, if you wanted to make it a standard, you might use XML or something similar. I'm actually a game programmer - and we use XML to save game state while we're working on the game - specifically because it makes it easier for us to cheat(!). If I want to sort out a bug that my play-testers tell me only shows up in level 10, I don't want to have to work through levels 1..9 to get there - and I might want a million health points and an unrealistically large mountain of ammo while I test it. When the game goes live, we switch to an encrypted format to avoid cheating - and the game no longer generates or understands the XML version. Increasingly, we store all of that stuff online in a cloud-server database. That's nice because it makes cheating much harder - and it has the nice side-effect that you can switch from playing on one computer to another and still retain your saved games. We can also use data analytics to find where levels are too easy or too hard - or to see if something is going awry someplace. SteveBaker (talk) 17:18, 29 January 2016 (UTC)

Recursively finding duplicates in a sequence that contains an increasing subsequence followed by a decreasing subsequence

Hello,

I'm studying for a test in an introductory CS course, and I have encountered the following question: Your'e given an array of length "size" of integers. The array starts with strictly increasing subsequence (every consecutive elemnt is stricly larger than the previous element), and then appears a strictly decreasing subsequence (every consecutive elemnt is stricly smaller than the previous element). Write a function that returns 1 if some element in the array appears twice, 0 otherwise. for example, the function should return 1 for [1,3,4,9,12,10,7,4,2] and 0 for [1,4,5,6,9,2].

The question is not difficult, and the solution is straightforward. However, they require the function to be recursive, and take advantage of the unique structure of the array. In addition, the array should not be sorted. I would appreciate any insight\direction towards a solution to this problem.

Thanks. 19:25, 28 January 2016 (UTC) — Preceding unsigned comment added by 31.154.161.109 (talk)

Here's how to do it using a loop - doing it using recursion is left as an exercise for the reader (bearing in mind that we're not supposed to answer homework questions directly):

   i = 0
   j = size - 1
   do until i == j
      if a[i] == a[j]
         return 1
      else if a[i] < a[j]
         i = i + 1
      else
         j = j - 1
      end if
    loop
    return 0

Tevildo (talk) 19:41, 28 January 2016 (UTC)

Thanks! after reading your answer I noticed the resemblance to the "merge" part of mergesort. 31.154.161.109 (talk) 20:03, 28 January 2016 (UTC)

January 29

How to find out whole SEO website report?

Hi, I am anayka and i am seo i want to how we can get whole seo report of any one website . Which is helping me to find out my working strategy for working next to ranking up my web site rank in search engine.

By anaya, — Preceding unsigned comment added by 27.109.11.70 (talk) 07:51, 29 January 2016 (UTC)

I've removed the link to your web site, as this is not the place to advertise it. Have you read our article on Search engine optimization? That describes several ways to improve your ranking. Also just googling the term will return several links to advice on how to do so. Rojomoke (talk) 09:30, 29 January 2016 (UTC)

Can you know absolutely everything about html?

Can you reach a point where you know absolutely everything about html? Or, are there still fringe cases where things break down in unexpected ways?--Scicurious (talk) 15:35, 29 January 2016 (UTC)

Even expert programmers still use the reference material! HTML relates to a quite extensive body of technologies, and it's fairly small by comparison to other technologies! Here's a link to the official HTML / CSS Standardization website, managed by the World Wide Web Consortium. To the extent that HTML behaves in a standard way, that site is the authoritative place to get information. One theme that recurs through web design is the constant effort required to deal with non-standard behaviors and extensions. For every great programmer who complies with the standards, there are many more "elite hackers" who have found clever and horrible tricks to do non-standard things with HTML: so the great cat-and-mouse game continues. The worst part is, some of these "clever enhancements" are built into major web browsers. Thus, web page authors have to work extra hard to make sure behaviors are correct across a wide diversity of user-platforms.

It is worth saying that if the depth of your knowledge about HTML only includes a knowledge of the markup language rules, then you are categorically excluding knowledge about network transactions, web servers, scripting languages, rendering engines, data security, and the like. Furthermore, HTML exists in contexts far beyond the application to web pages delivered via internet... again, if you want to know everything that has any peripheral relation to HTML, you'll need to spend a long time studying a diverse range of related technologies.

Generally, we can broadly categorize this expertise by hierarchically arranging technologies, e.g. using the OSI model. HTML is usually grouped as a "presentation layer" technology.

Nimur (talk) 16:03, 29 January 2016 (UTC)

It would be very surprising if the standard were sufficiently watertight that there were no unspecified cases. But even if the standard was completely and perfectly specified, in practice, it's unlikely that every browser programmer will have understood and implemented those specifications perfectly - so if you are determined to push the envelope, you'll very soon find that browser differences start to show up. The difficulty is that specifications are written in English - which is full of ambiguity and vagueness - so there is no way to test a particular implementation to verify that it meets the specification. Some standards (OpenGL comes to mind) include a supposedly comprehensive test suite - with the presumption that providing your implementation passes those tests, it's compliant with the standard. But gaps in the test suite leave ambiguity in the system. Another approach is to provide a "reference implementation" (MP3 does this) - and in cases of ambiguity in the English description, you can run your test case against the reference and whatever it does is "the right thing". But HTML has neither a comprehensive test suite, nor a reference implementation - so basically, it's down to hoping that there is no ambiguity in the English description...which there probably is. SteveBaker (talk) 16:51, 29 January 2016 (UTC)

There are subtle diffs in how HTML behaves on different platforms (and the version of O/S), as well as some things not being supported at all on some platforms. StuRat (talk) 17:46, 29 January 2016 (UTC)

Review this, could be helpful... -- Mr. Zoot Cig Bunner (talk) 19:42, 29 January 2016 (UTC)

I disagree with a theme through these answers. HTML is HTML. It is independent of a platform or browser or network capability... HTML is just text in a text file. It doesn't "behave" in any way. The HTML renderer will behave in a certain way when it parses HTML. So, the answers here are answering: "Is it possible to know everything about every HTML renderer?" That is a completely different question than: "Is it possible to know everything about HTML?" - limiting this to just knowledge of the tags and all attributes for those tags, ignoring how they might be rendered. 199.15.144.250 (talk) 20:01, 29 January 2016 (UTC)

But, your observation is not accurate: for example, the HTML 5 standard explicitly specifies "Common Infrastructure" and prescribes a recommended, standardized rendering scheme. Of course, those standarizations are couched in very careful language defining how HTML user-agents "must" behave: "User agents are not required to present HTML documents in any particular way." Even still, these peripheral technologies that pertain to HTML are still documented as part of the standard. HTML is not just text - it is a semantic language, and also encompasses many ways for humans and machines to use and interact with that language. Nimur (talk) 16:35, 30 January 2016 (UTC)

The documentation does suggest appropriate rendering. It is possible (but not likely) that someone could memorize that document. So, answering the question would be: "Yes. It is possible to know everything about HTML." However, the answers above claim that any way in which anyone in the world might decide to render HTML is intrinsically part of HTML itself. If you go with that definition of "HTML", then the answer has to be: "No. It is not possible to know everything about HTML because it is nobody knows of every single renderer implementation that currently exists and will exist in the future." So, in my opinion, it comes down to a pointless semantic argument. 47.49.128.58 (talk) 18:54, 30 January 2016 (UTC)

Our question is in two parts:

• Can you reach a point where you know absolutely everything about html?
• Or, are there still fringe cases where things break down in unexpected ways?

Clearly it's possible to memorize the HTML specification(s) - and I'm quite sure that there are plenty of people who know it well enough (albeit without memorizing it verbatim) to be able to know what it says on any given point. But that's not what we're being asked...the question is more about whether knowing the entire specification is sufficient to be able to predict how a document should appear when rendered. I don't believe that's the case - and per our OP's second question - I'm quite sure that there is sufficient ambiguity in the specification that there are cases where the resulting rendering is subject to interpretation of the rules by each browser author....where the differences in appearance are not the result of bugs, extensions or omissions in the implementation and are not in the permitted range of variation laid out in the spec. SteveBaker (talk) 17:25, 31 January 2016 (UTC)

I doubt that anyone can know everything about something like that these days. Back in the 1970s I believe I knew everything about Fortran IV and everything that was documented about CDC's extensions. But then when Fortran 77 came out and CDC changed their extensions, I never learned it all about either of those. Bubba73 ^{You talkin' to me?} 06:09, 1 February 2016 (UTC)

February 1

Recording videos

In Windows 8.1, how can one record on video what's happening on one's own computer screen? Does one need any external devices for this? 2601:646:8E01:9089:F88D:DE34:7772:8E5B (talk) 02:36, 1 February 2016 (UTC)

It appears that Screencam will do it. See Comparison of screencasting software for more options. Bubba73 ^{You talkin' to me?} 02:40, 1 February 2016 (UTC)

Thanks! 2601:646:8E01:9089:F88D:DE34:7772:8E5B (talk) 03:42, 1 February 2016 (UTC)

I would hope that at one point there will be a single keyboard button to do this, using a built-in function, just as Screen Print now grabs a single frame. StuRat (talk) 05:28, 1 February 2016 (UTC)

Probably not in the near future, because not all computers have the needed software. 2601:646:8E01:9089:F88D:DE34:7772:8E5B (talk) 07:41, 1 February 2016 (UTC)

How frequent brief charging affects phone battery life

I have a Samsung Galaxy S3 and a wonky charger. I think some of the pins might be missing or it's just a fraction too small. Sometimes it will flicker back and forth from charging and not charging, maybe even hundreds of times in a night. I feel like this is frying my battery, by essentially charging it in 1 second intervals dozens of times rather than one consistent charge. I thought I read somewhere that what kills the battery is charging it many times such as this. Detrimental or just tedious? NIRVANA2764 (talk) 03:18, 1 February 2016 (UTC)

This behaviour may affect the battery since it ideally should be charged with a CC-CV profile which isn't properly possible if it's been disconnected so often. However I would be more concerned about the affect on the phone. It's fairly unlikely it's designed for the charging to be connected and disconnected hundreds of times a day. Worst case you damage something causing the protection mechanism to stop overcharging to fail and risk a fire from the lithium ion battery. This may not be that likely, but I'm not sure how well the phone will have been tested for charging to be disconnected and reconned hundreds of times a day over long period. There's even greater concern if there is indeed an intermited connection. If it's on the phone side you definitely risk damaging something on the phone, permanently. If the intermited connection is on the power plug side, or inside the charger, there is a risk of fire or electric shock. (There's also a possibility the charger won't cope with such frequent disconnections and reconnects causing damage which could cause these or simply an unreliable supply to the phone which may result in the aforementioned possibilities.) I strongly suggest you throw out the charger. If you don't already have another USB charger, I suspect you're not using your phone to type this but a computer of some sort with a USB socket. If I'm correct, I suggest you connect your phone to your computer for charging until you get a new one. Nil Einne (talk) 05:44, 1 February 2016 (UTC)

N-trig Duo digitizer drivers?

Since N-trig was acquired by Microsoft, the drivers for their DuoSense digitizer have practically disappeared from the Internet. I have a Dell Latitude XT convertible tablet running Windows 8.1 that has this digitizer. Is it possible to find the Windows 8/.1 drivers somewhere? I have looked but cannot find them.