Hey, this is driving me nuts: I'm using a Thinkpad X13 with Pop and I have regular problems with my bluetooth mouse disconnecting. This seems to happen on random moments; sometimes I can use my system for hours before this happens, and sometimes it'll disconnect within minute.
When the disconnect occurs, I see the following in /var/log/syslog:
Jun 30 07:55:54 pop-os kernel: [195710.713293] usb 3-3: reset full-speed USB device number 77 using xhci_hcd
I've been using this to restart the connection, but it's not a solution:
sudo service bluetooth restart; sudo rfkill block bluetooth; sudo rfkill unblock bluetooth