firefox eats threads

[Thomas Klausner <wiz%NetBSD.org@localhost>]

Hi!

Over the last months I have noticed a pattern. When I leave a firefox
process running for some time, it reduces the available threads for
other programs. The symptom is that other programs (like git, gnucash,
or anything that needs threads) don't start or have weird failure
modes.

When I quit and restart firefox, there are immediately enough threads
available again. So I'm sure it's firefox-related.

Last night I noticed that this even happens when I'm not actively
doing anything in it (so perhaps extensions or firefox sync also have
an influence).

Did anyone else notice this?

Any ideas how to fix this?
 Thomas