My Cat Taught Me Browser Task Manager

My cat walked on my keyboard, and this happened ,

She launched the Microsoft Edge Browser Task Manager that I didn't know existed. Modern Web Browsers like Mozilla Firefox, Google Chrome, and Microsoft Edge are of multiprocess architecture. The Chromium projects have a good introduction about the advantage of this design and that I quote,

"

It's nearly impossible to build a rendering engine that never crashes or hangs. It's also nearly impossible to build a rendering engine that is perfectly secure.

In some ways, the state of web browsers around 2006 was like that of the single-user, co-operatively multi-tasked operating systems of the past. As a misbehaving application in such an operating system could take down the entire system, so could a misbehaving web page in a web browser. All it took is one browser or plug-in bug to bring down the entire browser and all of the currently running tabs.

Modern operating systems are more robust because they put applications into separate processes that are walled off from one another. A crash in one application generally does not impair other applications or the integrity of the operating system, and each user's access to other users' data is restricted.

"

So when a browser runs, it creates multiple processes. However, old fashioned as I am, I wasn't aware that Microsoft Edge browser had a tool to show and to help users manage the processes -- the keyboard shortcut to open Microsoft Edge Browser Task Manager is SHIFT + ESC. The cat must have stepped on the two keys and taught me this.  You can also launch it from the menu as the following screen shot shows, i.e., click at "...", select "More tools", and then "Browser task manager".

Sure enough, FireFox and Chrome browsers have the similar. In FireFox, open the menu, click "More", and select "Task Manager".

In Chrome, open the menu, click "More tools", and then select "Task Manager".

Neat!

Problem with Firefox's Always Openning Web Page Unintended When Creating New Tab

I somehow had a problem described in this post, that is, when I open a new tab in Firefox and the new tab always opens a Yahoo Search page regardless the "When Firefox Starts" and "Home Page" settings in the "Options" menu. I blame myself for not careful when installing software and browsing the web. I am looking for a fix.

Followed the post cited above, I did not find any hidden add-ons. The solution did not work for me although it worked for some according to the comments left on the post.

I eventually have a fix for this problem.

When I open "about:config" and search the word "Yahoo", I find that the setting "browser.tab.newurl" is pointing to a Yahoo search page. After I set the value of the setting as blank, the problem goes away.

By the way, the Firefox discussion forum have some good discussion on related issues.

Firefox Encountering "Secure Connection Failed" Error

I restarted Firefox (version 38.01) to visit a few secure sites, at present including live.com, and encountered an error  as follows,

Secure Connection Failed

The connection to the server was reset while the page was loading.

• The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.
• Please contact the website owners to inform them of this problem.

A screen shot is captured as follows,

This is actually a known problem, although it  took me a while to find out why it occurred and what a solution might be.

Apparently, the sites were still using older version TLS (i.e., TLS 1.0) that Firefox 37.0 or newer do not consider them as secure any more. See these two discussions.

To create a workaround for those web sites,  we will use Firefox's about:config page.

1.  In Firefox address bar, enter about:config and hit the Enter key to open the about:config page.
2. Search insecure_fallback_hosts and locate the setting for the attribute security.tls.insecure_fallback_hosts
3. Double-click on the attribute to update its value. The value should be the host names of the sites you encountered the "Secure Connection Failed" error. The value can contain multiple host names, separated by a comma (","). For instance, if you encounter the error for sites secure.foo1.com and www.foo2.net, the value would be secure.foo1.com,www.foo2.net.

This workaround works for me for a few sites. Be aware that Firefox has a discussion on addressing a similar problem; however, the solutions therein (e.g., rename or remove cert8.db) do not work for this particular error, i.e., the sites use older version of TLS (TLS 1.0).

Firefox iMacro Add-on Error (0x8000ffff NS_ERROR_UNEXPECTED)

I was running iMacro Add-on for Firefox on a Linux machine. iMacro reported the following error,

Error: NS_ERROR_UNEXPECTED: 
  Component returned failure code: 0x8000ffff (NS_ERROR_UNEXPECTED) 
  [nsIPrefBranch.getIntPref], line 6 (Error code: -1001)

I tried the same script on two Linux machines, the same error occurred. The versions of the two cases are as follows,

• iMacros for Firefox 8.8.2
• Firefox 33.0
• Ubuntu 14.04

A few others saw the similar problem, as reported here in Feburary 2014.

To verify the problem exists, you may run the demo script coming from iMaco add-on, such as, Loop-Csv-2-Web.iim by default at $HOME/iMacros/Macros/Demo-Firefox. In my case, running the demo program would yield the same error.

Apparently, no fixes exist. One suggested workaround is to use an old version of Firefix, as indicated in the discussion mentioned above.

We can download old versions of Firefox from here. I tried Firefox 27.0b9. It works fine with the iMacro demo scripts and my scripts.

Since you would probably have another copy of Firefox installed, it is important that you close all existing Firefox window and run the older version of Firefox using its path. In addition, it is also important to check "Never check for updates (not reocmmended:security risk)" from the Preference under the "Advanced" tab; otherwise, the old Firefox would automatically download updates and the updates would be applied when the old Firefox restarts. Below is the list of steps that I performed,

wget https://ftp.mozilla.org/pub/mozilla.org/\
firefox/releases/27.0b9/linux-i686/en-US/firefox-27.0b9.tar.bz2

tar -xjvf firefox-27.0b9.tar.bz2

firefox/firefox -preferences # disable updates

firefox/firefox

Firefox 64-bit Nightly, Google Account, and FireFtp Addon ...

I have been a long-time Firefox browser user. Recently I have started using Firefox 64-bit Nightly, the 64-bit Firefox browser that is still in testing.

My experience suggests that the 64-bit version appears to have a better performance when compared with its 32-bit counter part -- well, this is just my feeling and I don't have objective data to back it up; it could have been the result that I restarted the 64-bit version more often than I did with the 32-bit version that eventually became almost frozen and had to be restarted.

A definite beneift, perhaps, just a short-term benefit, is that I can continue to use my beloved FireFtp addon.  FireFtp addon somehow did not catch up with version updates of the 32-bit Firefox and is now disabled by the lastest version of the 32-bit Firefox. However, I found that the 64-bit Firefox does not have the problem.

Besides, my own experience is that the 64-bit Firefox is quite stable and it only crashed a few times in more than a month.

The only problem that I really need to deal with when I use the 64-bit Firefox is the problem with signing into any Google account, e-mail, blogger (this blogger), voice ... The problem is that  from time to time, when I tried to sign in a Google account after a restart of the 64-bit Firefox, the Google sites report an error,

Oops! Your browser seems to have cookies disabled. Make sure cookies are enabled or try opening a new browser window.

The error message puts the blames on "cookies". In fact, regardless, following the steps from Google Support, such as this one, how I enable cookies on the browser, remove any history, and cached items, the problem remains. Finally, I realize that it is not a probem  is not with the cookies at all.

The solution is quite simple -- it is the 32-bit Firefox. Whenver the problem occurs, I follow the steps below,

1. Close the 64-bit Firefox immedialy, no need to meddle with cookies, web histories, and caches;
2. fire up the 32-bit Firefox;
3. log onto any Google account once using the 32-bit Firefox;
4. and then close the 32-bit Firefox;
5. finally restart the 64-bit Firefox.

Eureka! Wahla! I can now sign in any Google accounts.

So what's wrong with Firefox 64-bit Nightly? The problem may not be with Firefox; instead it may be a problem with Google, as indicated in this bug report -- I guess in this case the 32-bit Firefox sets the values of the relevant attributes to those that Google expects.

Producing PDF document Compatible to Firefox Build-in PDF Viewer

Sometimes Firefox Build-in PDF Viewer does not render some PDF documents well, in which case, the PDF Viewer complains that the PDF document may not be displayed correctly.

A suggested method to correct it is to use external PDF viewer as suggested at Mozilla.

Web searches yield lots of discussions and the discussions are mostly how to find a way to display it correctly just like the above. Those discussions are on the "consumer" side.

However, if you are the on the side of producing and posting PDF documents online, you are probably more interested from beginning with in producing PDF documents that can be displayed correctly by the Firefox Build-in PDF Viewer.

As I investigate, this is not a trivial task. Generally, when the PDF Viewer does not display the document correctly, it is a result that the document contains certain feature which the viewer does not support. To generate a compatible PDF document to the viewer is not to use any unsupported feature that the viewer does not support. However, I failed to locate any document showing which feature is supported and which is not, including the project site at GitHub.

One method that worked for me at least in a few occasions is to use Firefox's Element Inspector.

When a PDF document is not displayed correctly, locate the element that is not displayed correctly or a nearby element to the element that is invisible as a result of not being displayed correctly, right-click the mouse and select "Inspect Element". Examine the element and elements nearby in the Inspector. If you examine them carefully, you may identify something suspicious. For instance, in FireFox 26.0, a PDF file saved in Microsoft PowerPoint is not displayed correctly. Examining it in the Element Inspector, I found out that the location of the problem and suspected that the font "Verdana" somehow could not be displayed correctly, as shown below.
 

By replacing font "Verdana" by a recognizable font, the problem went away.