https://support.mozilla.org/en-US/kb/changes-toolbars-and-window-sizes-are-not-saved You may have corrupt xulstore.json or Localstore.rdf file.

Close Firefox. Open your file browser to this hidden location:

• Mac: *~/Library/Application Support/Firefox/Profiles
• Linux: *~/.mozilla/firefox/Profiles
• Windows: %AppData%\Mozilla\Firefox\Profiles
• *C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles

Search for the above files. Then rename or delete them. Restart Firefox.

Yeah no, I've found all those articles... and tried all their solutions. Doesn't help.

Describe the issue in greater detail.

? I'm not sure how to describe it in more detail than I already have.

I start a new profile.

I open two or three URLs in two or three windows and change their sizes.

I set the browser to restore tabs and windows on restart.

I shut down Firefox. I restart Firefox.

The windows and their contents come back at the initial window size (*not* the size I left them at) in a stacked orientation, completely "forgetting"/disregarding their former sizes and layout.

In addition, any new windows I launch, even if the window I currently have focused when I open the new window is of a different size from the initial size, open with that set initial size, whereas before I started experiencing this issue, the new window would inherit the size of window focused when it was opened (as it should/as is expected).

How much more clear can I be?

Hi joeyconnick, as a Windows user, I find many workings of MacOS X mysterious. There is a file called a plist which may also influence how Firefox lays out on screen. If you search for threads about "org.mozilla.firefox.plist" on this forum (for example: 1084999) or on Apple's forums, perhaps they will help in determining whether removing that file might help and any other consequences it might have.

Hi jscher2000... not sure how you figured out I was on a Mac, but thanks for pointing me to the plist files. I tried deleting them but unfortunately, it didn't help.

The issue does seem to be impacted by uBlock Origin (a popular ad-blocking extension) as mentioned in 1084999 but even with that add-on fully removed, the windows do not properly remember their size or location on restart as they used to.

It's sad... Firefox used to be my go-to browser and I recommended it to a lot of people but first with its memory leak problems and now something like this (not to mention the upcoming blowing away of several key add-ons), I guess I'll just be using Chrome more and more now.

jscher2000 Could this another issue with v55?

How are you closing Firefox?

On Mac you may have to close (quit) the Firefox application while windows are still open to ensure that the window size is stored in xulstore.json.

You can also check this file to see if the main-window size and position gets stored.

Also make sure that you do not run Firefox in Private Browsing mode (never remember history).

You can check for problems with the sessionstore.js file in the Firefox profile folder that stores session data. When sessionstore.js is deleted you lose pinned tabs and open tabs and you will have to recreate them, so if necessary make a note or bookmark them.

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.

• Help -> Troubleshooting Information -> Profile Directory:
  Windows: Show Folder; Linux: Open Directory; Mac: Show in Finder
• http://kb.mozillazine.org/Profile_folder_-_Firefox

I'm closing with Firefox --> Quit Firefox, so it should definitely be storing window info. (That is, I'm not closing the windows first.)

I'm not running it in Private Browsing mode and I do not have "Never remember history" set.

Now I seem to be seeing slightly different behaviour... most window sizes/positions are restoring... EXCEPT for whatever Firefox has deemed the first window, which restores to the default size and position.

By "first" I mean say you have 3 windows open (Window 1, Window 2, Window 3).

When I restart, Window 1 does not remember its position or size and restores at the default size and position. The other two windows restore as expected.

If I close Window 1 before I quit Firefox, then on restart Window 2 appears to now be deemed the initial window and does not remember its position or size, instead restoring at the default size and position. Window 3 restores as expected.

So, in short, FF is pretty #@$%ed.

I'll try blowing away sessionstore.js and see if that helps.

Yep, deleting sessionstore.js doesn't help. Still back to the first window not remembering its size or position.

The window settings of other windows are likely stored in sessionstore.js, so that seems to be working. The first (main) window might be positioned by the operating system or otherwise use some defaults.

Yeah no, it's not "just a Mac" thing. It was working perfectly before, first window and all. And I haven't changed OSes, so it's not the OS that's doing it.

See if this helps any;

https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save

Note: Some software, like Advanced SystemCare with Surfing Protection, can protect files in the Firefox profile folder against changes. If you have such software then check the settings or uninstall this software.

Nope, none of this applies to me, and this is happening on a brand new profile.

However, I did the whole "Refresh Firefox..." thing and that seems to have worked so far. Had to resync everything and set a lot of stuff back up but so far *fingers crossed* it's working as expected.

If it works out, That was very good work. Well done. Please flag your last post as Solved Problem so others will know.

I have... although having to refresh the entire browser doesn't seem like a very viable solution to me for most people. It's a lot of work to restore things and if you haven't got Sync setup, that would be painful.

These can't get your data back, but will help in the future.

These add-ons can be a great help by backing up and restoring Firefox

https://addons.mozilla.org/en-US/firefox/addon/febe/ FEBE (Firefox Environment Backup Extension)

FEBE allows you to quickly and easily backup your Firefox extensions, history, passwords, and more. In fact, it goes beyond just backing up -- It will actually rebuild your saved files individually into installable .xpi files. It will also make backups of files that you choose.

https://addons.mozilla.org/en-US/firefox/addon/opie/ OPIE

Import/Export extension preferences

I had this problem starting with Firefox 55 as well. For me it was the "Improved Privacy Settings" addon which caused this problem. After uninstalling it Firefox started remembering my window sizes again.

I encountered the same problem with the Firefox 55 upgrade.

I found out that it is not Firefox itself but it has to do with something in the profile folder that was changed/updated.

I did a "refresh Firefox" and as expected all was fine. I created two additional profiles all was fine as well. When I imported my previous profile however, the problem is back!

I have version 55.0.3 64-bit Firefox running. when I start it with the newly created profiles the problem does not exist when I start Firefox with my old profile the problem is there!

So the $99,000 question now is, since Mozilla is not very forthcoming to publish where, in which file the window size is stored or reference to, which file or reference or a possible registry entry causes this!

https://support.mozilla.org/en-US/kb/changes-toolbars-and-window-sizes-are-not-saved You may have corrupt xulstore.json or Localstore.rdf file.

Close Firefox. Open your file browser to this hidden location:

• Mac: *~/Library/Application Support/Firefox/Profiles
• Linux: *~/.mozilla/firefox/Profiles
• Windows: %AppData%\Mozilla\Firefox\Profiles
• *C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles

Search for the above files. Then rename or delete them. Restart Firefox.