ArturPires wrote:What I think is strange is that, apparently, few people had this problem.
I identified the following theoretical (*) workflow to get into this problem:
Create a VM with VirtualBox 5.1 or earlier, so that the default
Recording settings are written to the
.vbox file. Then create a snapshot, so that those settings are preserved in the
.vbox file. Update VirtualBox "over the years" up to 6.1.36, and you'll run into the issue today.
There are alternatives to that workflow, for example when actively using the
Recording feature (leading to non-default settings), but I guess that the majority of today's VMs were created later than in the VirtualBox 5.1 time and never configured the
Recording feature.
(*) A few years ago, in my early VirtualBox user days, I already noticed the "large" value of the
screens attribute, but I didn't investigate it then. Yesterday, I only modified a current
.vbox file to reproduce the issue, so I didn't exactly prove my theory above.
mpack wrote:What problem did the OP have, since it looks unlikely it would be the same as ArturPires.
I don't see any information from the OP that contradicts my explanations. Why do you think it's unlikely to be the same issue?
mpack wrote:How come ArturPires had the problem twice? (we don't appear to have both .vbox files).
The VirtualBox Manager starts the
VBoxSVC process, which reads in all
.vbox files. If any one of them contains the "bad" information, the problem occurs. ArturPires identified two VMs triggering this behavior, by selectively adding them to an testing installation. Or did I misunderstand your question?
mpack wrote:How did number of screens come to be set to that particular number?
First of all, 18446744073709551615 == 0xFFFFFFFFFFFFFFFF == 2^64-1 is a 64-bit bitmask with all bits set, and most of the VirtualBox code handles it as such. Only some part of the new VirtualBox 6.1.36 changes interpret it wrong.
The default value 18446744073709551615 simply enables the screen recording on all (up to 64 possible) virtual screens. Although I'd suspect that VirtualBox wouldn't be very fast if you'd really try to use 64 virtual screens.