You only see a reset button on the Help > Troubleshooting Information page if you are using the profile that is marked in the profiles.ini file as the default.
So if you use a desktop shortcut to start with a specific profile (-P "profile") and you need to use a copy that doesn't specify the profile, but only has a -P appended to get the Profile Manager.

Can you start Firefox in Safe Mode?
You can append the -safe-mode switch to the command line in the Firefox desktop shortcut.

Did you try a new profile? Create a new profile as a test to check if your current profile is causing the problems.

See "Creating a profile":

• https://support.mozilla.org/kb/profile-manager-create-and-remove-firefox-profiles
• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues

If the new profile works then you can transfer some files from an existing profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over the problem.

• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

The only profile is .default. Firefox will start in SAFE MODE. About:crashes is empty. Crash Reporter is absent.

I had to do a clean and reinstall of FF-26 absent the RESET function-button on the troubleshooting page or an exhaustive list of particular files to delete.

Thanks for your continued attention to my peculiar problem.

If it works in Safe Mode and in normal mode with all extensions (Firefox/Tools > Add-ons > Extensions) disabled then try to find which extension is causing it by enabling one extension at a time until the problem reappears.

Close and restart Firefox after each change via "Firefox > Exit" (Windows: Firefox/File > Exit; Mac: Firefox > Quit Firefox; Linux: Firefox/File > Quit)

• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

In Firefox Safe mode these changes are effective:

• all extensions are disabled
• default theme is used (no persona)
• userChrome.css and userContent.css are ignored
• default toolbar layout is used (localstore-safe.rdf)
• Javascript JIT compilers are disabled (javascript.options.*jit)
• hardware acceleration is disabled

• plugins are not affected
• preferences are not affected

It works in SAFE MODE, I can access Wikipedia without crashing.

In normal mode with EXTENSIONS *disabled* - Adblock Plus, Ghostery, Troubleshooter - accessing Wikipedia crashes the browser FF-26.

Next would be to disable hardware acceleration.

You might need to restart Firefox in order for this to take effect, so save all work first (e.g., mail you are composing, online documents you're editing, etc.).

Then perform these steps:

• Click the orange Firefox button at the top left, then select the "Options" button, or, if there is no Firefox button at the top, go to Tools > Options.
• In the Firefox options window click the Advanced tab, then select "General".
• In the settings list, you should find the Use hardware acceleration when available checkbox. Uncheck this checkbox.
• Now, restart Firefox and see if the problems persist.

With hardware acceleration unchecked DISABLED my FF-26 crashes accessing a Wikipedia page. Also with all extensions disabled.

With respect and my thanks, I tried all of the boilerplate troubleshooting that I could find before I asked for help. But I will do as I am asked as I can to assist. Thanks.

Does it has effect if you toggle the javascript.options.*jit prefs to false on the about:config page?

• http://kb.mozillazine.org/about:config

You may have to close and restart Firefox after changing these prefs.

The closest that I have at about:config is javascript.options.jit_hardening

Nothing with .*jit - "dot wildcard jit" or "dot stuff jit"

You can enter this wild card in the Search bar at the top of the about:config page to see matching prefs.

• javascript.options.baselinejit.chrome
• javascript.options.baselinejit.content
• javascript.options.jit_hardening

OOps, sorry you're right. Which, chrome or content, toggle to false?

An answer to someone else's question on PDF preview in FF crashing, change in PREFERENCES Applications to document-viewer.

Try to set all three to false to see if it has any effect.

If that works better then try to toggle one at a time to true to see which is causing it.

Note that disabling the JIT compiler for content will have negative effect on JavaScript intensive pages.
The chrome prefs effects JavaScript code that runs in extensions and the Firefox user interface.

• javascript.options.ion.chrome
• javascript.options.ion.content

You can see here what gets disabled in Safe Mode:

• http://mxr.mozilla.org/mozilla-release/source/dom/base/nsJSEnvironment.cpp#764
• http://mxr.mozilla.org/mozilla-release/source/dom/base/nsJSEnvironment.cpp#695

Setting javascript.options.baselinejit.content to FALSE (with .chrome and .jit_hardening still TRUE) apparently ended the crashes on accessing the Wikipedia.

Will there be other side effects from this state? Can you explain in layman's terms the effect?

I am about to quit for the day. I'll mark it solved tomorrow barring more evidence. Thank you very much for your patience.

If setting javascript.options.baselinejit.content false helps then you hit is bug in the code produced by the JIT compiler for code used on web pages.

• http://kb.mozillazine.org/Firefox_crashes#JIT_compiler

Thank you for your assistance. My issue has been marked as solved.