For me, Firefox seems to remember the scroll position on some pages I've re-opened from earlier sessions, but I haven't done a test to make sure it's actually the correct position.

Do you notice this problem on particular sites? The reason I ask is that some pages are populated dynamically, like the Facebook news feed. I'm not sure whether Firefox can accurately restore position on those kinds of pages. I'm thinking in particular of pages that load more content as you scroll down. When Firefox reloads the page, the content you were viewing might not be loaded immediately. Therefore, when Firefox tries to scroll to the saved position, it may not exist yet so it scrolls to some other location. Because Firefox can't scroll down to the old position, that content doesn't get reloaded. Sort of a chicken and egg problem... but this wouldn't affect most sites.

I' am fairly sure its not that. Also what was responsible for tracking placement on the page?

This happens on pages where it is static nothing new is being loaded I did not have this problem on Firefox 24. I'm thinking its some kind of bug. For some reason it cant restore the correct position.

A way to duplicate what I'm talking about is to be able to save and quit so have another tab open find a webpage that is not populated dynamically. Scroll down to half way its easier to tell if its moved at this spot now close the tab and if you open it immediately its where you left it but if you close it again wait about 10 minutes open it again and it will have moved. This also applies to closing Firefox as well. At times it will stay others it won't its like a 50/50 chance that it will be where you left it after closing Firefox. This is a problem considering when you close Firefox and come back the next day the position has moved and lost where you last had it.

In case you are using "Clear history when Firefox closes":

• do not clear the Cache (note that Firefox will disable the disk cache in this case, see about:cache)

• Tools > Options > Privacy > Firefox will: "Use custom settings for history": [X] "Clear history when Firefox closes" > Settings
• https://support.mozilla.org/kb/Clear+Recent+History

Note that clearing "Site Preferences" clears all exceptions for cookies, images, pop-up windows, software installation, and passwords.

Clearing cookies will remove all specified (selected) cookies including cookies with an allow exception that you want to keep.

I don't know what changed between Firefox 24 and 25 but 24 did not have this problem this problem only happened after I updated to 25. I'm leery or doing a clean install considering I've seen people having 25 not working or crash after clean install. I would rather just go back to 24 if I can go back please let me know how to. Could this new update be messing with the profile?

This was happening before I cleared the cache at all thinking that was it. I do not have that option selected. How do I enable disc cache again. I'm not sure what I'm looking for in about:cache, what am I looking for that would tell me if its not enabled but as far as I can tell looks normal. Is it the offline storage cache? currently its at 0. Offline Cache is just empty. Also looked at some details for Memory Cache service has last modified 2013-11-08 14:03:34 but is telling me it expire at 1969-12-31 17:00:00. Could this be the problem and if so how do I fix it. I'm getting the same for Disk cache device but some say expire 1969 some say 2013 one said it expires at 2014. Does this help at all in finding the problem.

Where would I modify site preferences to keep where I scrolled on a page?

Do you see a disk cache section on the about:cache page?

Note that the offline cache is a different cache, you should see three cache sections (memory, disk, offline) on the about:cache page.

I see those but what do i do with them? I removed my name and profile name from the cache directory line for the sake of this post. Yes nothing is missing from the cache directory line. Memory cache device Number of entries: 27 Maximum storage size: 32768 KiB Storage in use: 46 KiB Inactive storage: 46 KiB List Cache Entries Disk cache device Number of entries: 1568 Maximum storage size: 358400 KiB Storage in use: 358158 KiB Cache Directory: C:\Users\\AppData\Local\Mozilla\Firefox\Profiles\\Cache List Cache Entries Offline cache device Number of entries: 0 Maximum storage size: 512000 KiB Storage in use: 0 KiB Cache Directory: C:\Users\\AppData\Local\Mozilla\Firefox\Profiles\\OfflineCache

It's gotten worse now it will move position as I'm on the page. Here is what happened i was on another tab doing something went back to a tab that was still open and active and it scrolled up to previous spot. I have already run a scan with antivirus software trust me when I say I got some good software for this, nothing came up what is the issue. For the love of all that is good just give me back Firefox 24 with none of these issues. Also what the is the default max storage in the post before this one currently is 350mb or 358400Kib, is this normal and if not what can I do about it. At the top of post this has only happened once don't know what caused it.

I've got the same problem. I found that page on which I scrolled down before updating FF to v25 get restored to that point. But new pages wont. Also the old ones only reload at the v24 scroll position.

IMO the scroll position is not being recorded in v25.

I've played with this for about 90 minutes in a new profile (i.e., default settings and no extensions). It does seem flaky in my testing.

• In a new tab, Firefox generally records and restores the scroll position normally.

• In a restored tab, Firefox usually fails to record the updated scroll position for a restored page and more often than not will continue to restore the originally saved position.
  • Reloading the page doesn't seem to change this.
  • Doing a "hard" reload bypassing the cache (Ctrl+Shift+r) stores the top of page as the scroll position.
  • Clicking a link to another page and clicking a link back to the stored page usually triggers the default behavior of recording position again. (I didn't test the back button, because I doubt that would work.)

Searching on the bug tracking system, I found a recent bug that sounds relevant: 921942 – Scroll position isn't restored in background tabs after session restore. I think I was testing in the "foreground" tab (i.e., the active tab when exiting and restoring). So it might be the same or something different.

Note about the bug tracking system: If forum members can contribute to the development, please feel free to pitch in. Otherwise, it's generally not helpful to add comments to bugs, but you can register on the Bugzilla site and "vote" for them to be fixed. See:

• Bugzilla Etiquette
• Voting

This is just for background, and probably isn't the complete story.

Firefox 25 included a change to how session data is saved. Because saving huge sessions degrades performance, even to the point of some people experiencing an ongoing series of little freezes, Firefox 25 made a number of changes aimed at making it more efficient. The problem with updating scroll position could be related to one of these changes.

Bugs I found that I don't fully understand:

• 887394 – [Session Restore] Don't collect state right after startup when restoring the initial session - change in Fx25
• 891360 – Move SessionStore I/O logic to a dedicated worker - change in Fx25
• 894993 – [Session Restore] SessionWorker takes lots of memory. - change in Fx25
• 886447 – [Session Restore] Optimize communications - not completed

hello jscher, after you've dug out https://bugzilla.mozilla.org/show_bug.cgi?id=921942 I managed to get a regression window with the STR mentioned there and it appears to be indeed related to session restore.

I checked the links provided noticed they were talking about a patch? Can I download that from somewhere? or do I wait for a Firefox 25.1 release or something similar for download?

Hi Nshelp, unfortunately, most of those pages refer to pre-Firefox 25 changes. I don't think there is a patch for this new issue in Firefox 25.

I tried to recreate your experiment jscher2000 and found the same. Active tabs scroll positions are stored. Background ones are not.

I hope this will be fixed with a .1 patch soon, but in the end I can work around the issue for a while.

But I thought they were referring to Firefox 25 issues. Do you know of any other recent bug related activity related to this.

Hi Nshelp, the first bug I linked is currently in development, the other four are completed and were changes made between Firefox 24 and Firefox 25. That's all I know.

jscher2000 would you know when the new release would be out?

Hi Nshelp, a new version of Firefox is released every 6 weeks, but this kind of change may take 2-3 versions to get into the main release, so it could be a while. Hopefully someone will come up with a workaround in the meantime.