Then you need to contact the Addon developer and tell them of their Addon issues. And provide them the crash error if there is one so they will look into the issue and address the problem.

How can I report a bug? If the System crashes, it can never register anything due to complete "Out Of Memory! I previously told the developer about this problem, but I was simply ignored.

They should have if they are on Firefox Addon page a link to their site to contact them. Did you look there as well. Even if the crash didn't register it's up to the user to report the issue to the Addon developer. And as you stated they ignored your question so that is out of the hands of Firefox since this is their issue not a Firefox issue.

System Windows pomyślnie zdiagnozował warunek braku pamięci wirtualnej. Następujące programy zużywają większość pamięci wirtualnej: firefox.exe (9200) zużywa 65063718912 b, firefox.exe (14040) zużywa 5101801472 b i msedge.exe (11512) zużywa 697122816 b.

 - MemoryExhaustionInfo 

 - SystemInfo 

  SystemCommitLimit 84604551168 

  SystemCommitCharge 84337549312 

  ProcessCommitCharge 77134929920 

  PagedPoolUsage 488992768 

  PhysicalMemorySize 68498423808 

  PhysicalMemoryUsage 67243077632 

  NonPagedPoolUsage 743378944 

  Processes 226

I've been using this extension for many years without noticing a memory problem. I do not have it set to translate sites or languages automatically, except for one particular site that I only use for specific research and do not leave open when I don't need it. Maybe yours is set to do more stuff automatically?

By the way, are you finding the built-in Firefox Translation feature useful as an alternative? I don't think it is up to the level of Google, yet, but maybe it's good enough? More info in this article: Firefox Translation.