I usually have many tabs open and that wasn't much of a problem before Firefox updated to Firefox Quantum and when the TabMix Plus AddOn was still working. However now Firefox has become barely usable for me mainly due to its RAM heavy session-restores which take a lot of time.
I tried a lot of things to solve this issue and read many posts about this problem online as a lot of people seem to have similar problems with Firefox Quantum. But it seems the only thing that really somewhat works with a large number of open tabs is the Tab Session Manager AddOn + the Tree Style Tab AddOn.
I hoped the Tab Session Manager AddOn would fix these issues in later versions, but it didn't: it still takes a lot of time to restore a session and Firefox still takes up a lot of RAM. (In addition the AddOn either crashes the browser or closes most of my tabs whenever it suddenly updates.)
I already disabled
Supports Tree Style Tab and enabled
Tab lazy loading in its options and have set
browser.sessionstore.restore_tabs_lazily set to true in about:config.
When restoring a session it loads
moz-extension://extension-id tabs with the extension-id as title and a loading animation as favicon. Running
sudo tcpdump -X -s0 -w /tmp/browser_start and opening that file in wireshark shows that Firefox does a lot of requests when restoring a session. Whatever Firefox and the Tab Session Manager AddOn are doing when restoring a session: it takes way too much time and occupies too much RAM.
Is there any way / software to get the Firefox browser to reliably and quickly save and restore nothing but favicon, url and page title in session backups?
I wouldn't want to have it initiate any DNS-requests or reload the latest favicons or anything else and I don't see why it wouldn't be possible to have Firefox restore a session with hundreds of tabs including their cached favicons within seconds and with it taking up less than a gigabyte RAM.
Often people recommend just bookmarking tabs instead of having them open but I'd like my tabs to be shown as regular tabs until I close or bookmark them. (I don't see why having many tabs open should be problematic: in a world in which computer game graphics become increasingly indistinguishable from reality simply having a browser with many tabs open for research should certainly not overstrain a modern PC. All of this shouldn't even require AddOns.)
If that's currently not possible I'm interested in why that is. If Firefox itself really doesn't offer this capability I'm also interested in for example FOSS forks that do and links to relevant issues.
I'm running Debian 9 with KDE and am using Firefox-esr 60.3.
tl;dr: is there any way or software to get Firefox Quantum to save and restore nothing but favicon, url and page-title in session backups so that RAM-usage and session-restores take less time and RAM when having many open tabs?