Separate Security Issue, please update your Flash 28.0 r0 by removing it with this tool : https://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html If you use it Reinstall with Flash Player Version: 30.0.0.134 Current Version https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, . . . .) Note: Other software is offered in the download. <Windows Only>

Hi, please try Safe Mode to see if it is a Extension that may be causing that to happen. SAFE MODE

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

In Firefox Safe mode these changes are effective:

• all extensions are disabled (about:addons)
• default theme is used (no persona)
• userChrome.css and userContent.css are ignored (chrome folder)
• default toolbar layout is used (file: localstore-safe.rdf)
• Javascript JIT compilers are disabled (prefs: javascript.options.*jit)
• hardware acceleration is disabled (Options > Advanced > General)
• plugins are not affected
• preferences are not affected

TEST''''is issue still there ?

If still there try this : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

• https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles
• https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer

Reinstall with Current Release Firefox 61.0.1 with a Full Version Installer

• https://www.mozilla.org/firefox/all/

Please let us know if this solved your issue or if need further assistance.

Thanks for your reply. I'm going to try all of the steps you suggested. I would also like to mention that the same thing (Page Bookmark Window closes too soon and defaults to Other Bookmarks in menu) happened on 4 other computers in addition to mine. The other 4 were in a completely different location, using a different connection to the Internet, and 3 of the 4 belonged to other people (one was a Windows 7 laptop that I lending to someone). Also, earlier this evening I tried opening the Bookmark This Page using Ctrl + D, and the Page Bookmark Window stayed open a bit longer than when I choose that from the Bookmarks menu. It still defaults to the Other Bookmarks folder, though. I'll post back when I have more information. Thanks again for your reply.

Hi, when you click on 'Bookmark this page,' Ctrl+d or the bookmarks star, the bookmark, by default - which cannot easily be changed (but see below), will go into 'Other Bookmarks' (prior to v48 known as Unsorted Bookmarks); however if you wish it to go to a different destination, keep your mouse pointer over the dialog box to prevent it from disappearing, then use the upper, downward pointing arrow on the far right, to select a destination > Done.

It's easier to click the star, otherwise you have to move the mouse pointer quite quickly to over the bookmark dialog dropdown before it auto selects Other Bookmarks and disappears!

You could have a look at this extension, which might be of help https://addons.mozilla.org/en-US/firefox/addon/default-bookmark-folder/

It isn't a bug or fault - that's how it's supposed to be! If you want to leave feedback for Firefox developers, you can go to the Firefox Help menu and select Submit Feedback... or use this link. Your feedback gets collected by a team of people who read it and gather data about the most common issues.