Thunderbird leaves LD_LIBRARY_PATH set when invoking firefox to open a clicked link. Firefox then crashes, because the thunderbird-bin libraries are preferred. Hacky fix: patch /usr/bin/firefox to unset LD_LIBRARY_PATH.
It works fine for me... Opening a link from thunderbird-bin opens in firefox (non-bin) just fine.
I have firefox-105.0.2 and thunderbird-bin-102.3.2. thunderbird's env contains: LD_LIBRARY_PATH=/opt/thunderbird stracing thunderbird when clicking the notification link to this bugreport yields in some subprocess: execve("/usr/libexec/gio-launch-desktop", ["/usr/libexec/gio-launch-desktop", "firefox", "https://bugs.gentoo.org/show_bug.cgi?id=876861"], 0x7f435f5d8400 /* 104 vars */) = 0 brk(NULL) = 0x555c2a54d000 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f0763eee000 [...] execve("/usr/lib64/firefox/firefox", ["/usr/lib64/firefox/firefox", "https://bugs.gentoo.org/show_bug.cgi?id=876861"], 0x5595d72266d0 /* 106 vars */) = 0 [... loads many libraries and tries LD_LIBRARY_PATH first] openat(AT_FDCWD, "/opt/thunderbird/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/usr/lib64/firefox/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3 [...] openat(AT_FDCWD, "/opt/thunderbird/libssl3.so", O_RDONLY|O_CLOEXEC) = 4 [... no other tries for libssl3.so, even though we should use /usr/lib64/libssl3.so from dev-libs/nss] write(2, "XPCOMGlueLoad error for file /usr/lib64/firefox/libxul.so:\n/opt/thunderbird/libssl3.so: version `NSS_3.80' not found (required by /usr/lib64/firefox/libxul.so)\n", 160) = 160 [...] write(2, "Couldn't load XPCOM.\n", 21) = 21 [...] exit(255) so firefox is using thunderbird-bin's libssl3.so which is incompatible. if I unset LD_LIBRARY_PATH in the firefox launch script, all is well.
(In reply to Joonas Niilola from comment #1) > It works fine for me... Opening a link from thunderbird-bin opens in firefox > (non-bin) just fine. Whether or not it's "safe" depends on your exact versions of both.
Same problem here XPCOMGlueLoad error for file /usr/lib64/firefox/libxul.so: /opt/thunderbird/libnss3.so: version `NSS_3.101' not found (required by /usr/lib64/firefox/libxul.so) Couldn't load XPCOM.