The crash test for bug 1800470 triggered also this crash

0 XUL!PLDHashTable::EntryStore::IsAllocated() const [PLDHashTable.h:779cf97ae5dee13b3527169a9745553f9957a15e : 325]
Found by: inlining
1 XUL!PLDHashTable::Remove(void const*) [PLDHashTable.cpp:779cf97ae5dee13b3527169a9745553f9957a15e : 532 + 0x0]
rax = 0x0000000129205930 rdx = 0x0000000000000008
rcx = 0x0000000000000000 rbx = 0x0000000129bf6a38
rsi = 0x000000012384c7a8 rdi = 0x00000000000000c0
rbp = 0x0000700006202890 rsp = 0x0000700006202840
r8 = 0x0000000000000000 r9 = 0x0000000000000008
r10 = 0x0000000000000010 r11 = 0x0000000108942b00
r12 = 0x000000012384c760 r13 = 0x0000000000000003
r14 = 0x0000000000000003 r15 = 0x0000000000000000
rip = 0x00000001081e53a1
Found by: given as instruction pointer in context
2 XUL!mozilla::ipc::IProtocol::DestroySubtree(mozilla::ipc::IProtocol::ActorDestroyReason) [ProtocolUtils.cpp:779cf97ae5dee13b3527169a9745553f9957a15e : 585 + 0xc]
rbx = 0x0000000129bf6a38 rbp = 0x00007000062028e0
rsp = 0x00007000062028a0 r12 = 0x000000012384c760
r13 = 0x0000000000000003 r14 = 0x0000000000000003
r15 = 0x0000000000000000 rip = 0x000000010893ff0d
Found by: call frame info
3 XUL!mozilla::ipc::IProtocol::DestroySubtree(mozilla::ipc::IProtocol::ActorDestroyReason) [ProtocolUtils.cpp:779cf97ae5dee13b3527169a9745553f9957a15e : 573 + 0x7]
rbx = 0x0000000000000000 rbp = 0x0000700006202930
rsp = 0x00007000062028f0 r12 = 0x0000000129bf6a00
r13 = 0x0000000000000003 r14 = 0x0000000000000003
r15 = 0x0000000000000001 rip = 0x000000010893fee7
Found by: call frame info
4 XUL!mozilla::dom::PFileSystemManagerParent::OnChannelClose() [PFileSystemManagerParent.cpp: : 1179 + 0x9]
rbx = 0x0000000129bf6a00 rbp = 0x0000700006202950
rsp = 0x0000700006202940 r12 = 0x0000000000000000
r13 = 0x0000000129b08c90 r14 = 0x000000011a3ebc70
r15 = 0x0000000000000000 rip = 0x000000010a0b7b43
Found by: call frame info
5 XUL!mozilla::ipc::MessageChannel::OnNotifyMaybeChannelError() [MessageChannel.cpp:779cf97ae5dee13b3527169a9745553f9957a15e : 2034 + 0x7]
rbx = 0x0000000129bf6a78 rbp = 0x0000700006202990
rsp = 0x0000700006202960 r12 = 0x0000000000000000
r13 = 0x0000000129b08c90 r14 = 0x000000011a3ebc70
r15 = 0x0000000000000000 rip = 0x00000001089357d1

Bug 1800376 was also filed for this crash.

Based on the conversation on Matrix, janv is looking into this.