Diễn đàn hỗ trợ Firefox

A friend (who knows even less about technology than me) has an old Dell Inspiron 1501 which has been running Linux Mint 18 Xfce, which is now unsupported. I'm beginning to regret it but just to keep it going for a couple of years I offered to update to Mint 20 Xfce, which is the last version listing 1 Gb as the minimum Ram (everything later or other version are 2 Gb or more), which is the most that system can use. Once the wifi was eventually working (old b43 broadcom driver) most things went fine (except Team Viewer, which works on another Mint 20 Xfce system, but that's not a question for here). However, she uses Yahoo mail, and for some reason just attempting to load the login page (login.yahoo.com) causes Firefox to crash (I mentioned Thunderbird in the title as I attempted to access Yahoo Mail with it, but because it needs to access the Yahoo Mail page (as I think this is now based on App codes rather than passwords), and doing that crashed Thunderbird also). I'm pretty sure I have methodically gone through all the troubleshooting steps on https://support.mozilla.org/en-US/kb/troubleshoot-and-diagnose-firefox-problems (clear cookies & cache by deleting history; clear startup cache; refresh; reinstall; new profile). Firefox doesn't crash in Troubleshoot mode, despite the fact is seems to still use hardware acceleration, even though I thought it would disable that. Hence, I'm at the end of what I know to try (and that's just from following the guide, I am not an expert) and would be grateful for any help anyone can offer. I attach an image that lists all the submitted crash reports, as they will refer to slightly different conditions as I tried all the options mentioned above. I'm using my own PC to submit this (so any hardware & system data submitted by this web-form won't be relevant), not the Inspiron 1501 that has the issue. I can open the Yahoo mail page on this machine (same version of Firefox) and also on the Inspiron 1501 using Chrome (but there was a different reason relating to security why we couldn't log in via that). Would really like to get Firefox (and Thunderbird) working on the laptop, if possible.

I lost my tabs. Firefox has been opened and closed several times after losing tabs. I went here https://www.jeffersonscher.com/ffu/scrounger.html. I was able to find the file containing my lost tabs, it is sessionstore(1706800631216_9931f324-5558-4488-a36c-a5b3cb9e8c54_event_jsonlz4).json What do I do with this file now? Thank you.