Disregard. Edited above to include what was added here.

Make sure your Java (Not JavaScript) is up to date Verify Java and Find Out-of-Date Versions {web link}

Version 8 Update 66 Release date November 16, 2015 http://java.com/en/download/manual.jsp

https://java.com/en/download/help/ Java Help Center

Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac=Options) key, and then starting Firefox. Is the problem still there?

Thank you Fred. This appears to have solved the problem. I remember getting rid of java some time ago, thought I'd only downloaded it for a particular task, and didn't need it. ha. Very happy to have these pages loading without a glitch. :-)

Unfortunately, I'm again having problems, hanging while loading. Any idea what I should try next? thanks

Have you checked the Java Help Center?

You can check for problems with preferences.

Delete possible user.js and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in current Firefox releases.

• http://kb.mozillazine.org/Preferences_not_saved
• http://kb.mozillazine.org/Resetting_preferences

Start Firefox in Safe Mode to check if one of the extensions (Firefox menu button/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

• Switch to the DEFAULT theme: Firefox menu button/Tools > Add-ons > Appearance
• Do NOT click the Reset button on the Safe Mode start window

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

FredMcD said

Have you checked the Java Help Center?

Thanks. I just went there, looked at my plug-ins, and Java was set on 'Ask to Activate'. I changed it to always activate, will see if this does the trick.

cor-el [[#answer-831908] Thank you. if the above does not work, I'll follow your suggestions.

• I went to Java Help, and saw that my Java applet wasn't activated. I activated it, but this did not help.

• I Disabled Add-ons. But this did not seem to show me anything.

• I looked at my add-ons, and it looks like it would take forever to try turning each one off and checking for the problem. I chose the one I thought might be the most likely: Privacy Badger. But this has not changed anything, sitll hanging, I'm having to force-quit.

What else I've done:

• Delete Duplicate Session Restore files
• Turn off Hardware Acceleration

Can you advise which of the 2 procedures I'm listing below is the next best step? I haven't wanted to go deleting things until I'd done other possibilities. Is the 2nd one, cor-el's suggestion, going to reset all my style and extension preferences? so I have to load everything back in again?

In the Firefox profile folder, find and rename the files places.sqlite to places.sqlite.old and places.sqlite-journal to places.sqlite-journal.old (if it exists).

Delete possible user.js and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in current Firefox releases

I'm not finding these prefs, neither in my Finder (OSX), nor in about:config. In about:config I get the 2 lines I'm attaching as file. In Finder, I get a text doc, 2nd attachment.

ADD: I can't upload the Grab files. :-(

I must be missing something, probably something obvious. thanks for helping.

This afternoon I installed places maintenance extension. It said no problems. But still, when I look in about:config, there is no places.sqlite.

• If you have many extensions then first enable half of the extensions to test which half has the problem.
• Continue to divide the bad half that still has the issue until you find which one is causing it.

places.sqlite and places.sqlite-shm and places.sqlite-wal are file in the Firefox profile folder and not prefs stored in prefs.js.

The point with (temporarily) renaming/moving or deleting files in the profile folder is to check for issues caused by specific data stored in this file. The prefs.js file stores setting that you make in Options/Preferences among other data.

In the Firefox profile folder, find and rename the files places.sqlite to places.sqlite.old and places.sqlite-journal to places.sqlite-journal.old (if it exists).

OK, found places.sqlite in pref folder, renamed .old. No other places. files.

No user js; no numbered prefs-##.js files;

rename (or delete) the prefs.js file I added .old.

That's enough for tonight, I'll be re-starting and see how it goees tomorrow.

Is it possible this is caused by too many tabs? I've read numerous references to hundreds of tabs, so I'm certainly not the only one. The bulk of my tabs are not loaded.

Thanks cor-el.

So far, in my first attempts at AM news, this seems to have helped considerably, I was worried I'd lose all my settings, bookmark bar, but happily that's all intact. I'll leave this question open for the next day or so, see how it goes. Thanks.

My problem seems almost fixed. I'm not needing to use YesScript for Guardian anymore, but am still having occasional slow-downs, hanging. Any suggestion of what I should do next? Go through all the extensions? Thanks for your help.

I'm closing this question. Problem seems solved. Minor slow-downs continue, but nothing like the hanging problems of earlier. If I get annoyed enough, I'll go through the extensions at a later date. Thanks for your help.