Exception when clicking Sync too fast

Seems clicking on Sync too rapidly tries to start it twice, leading to this error. No actual effect.

Anki 2.1.31 (177ced7a) Python 3.8.5 Qt 5.15.0 PyQt 5.15.0
Platform: Linux
Flags: frz=False ao=True sv=2
Add-ons, last update check: 2020-08-18 20:30:07

Caught exception:
Traceback (most recent call last):
  File "/usr/lib/python3.8/site-packages/aqt/taskman.py", line 87, in _on_closures_pending
  File "/usr/lib/python3.8/site-packages/aqt/taskman.py", line 59, in <lambda>
    lambda future: self.run_on_main(lambda: on_done(future))
  File "/usr/lib/python3.8/site-packages/aqt/taskman.py", line 76, in wrapped_done
  File "/usr/lib/python3.8/site-packages/aqt/sync.py", line 99, in on_future_done
  File "/usr/lib/python3.8/site-packages/anki/dbproxy.py", line 34, in begin
  File "/usr/lib/python3.8/site-packages/anki/rsbackend.py", line 227, in db_begin
    return self._db_command(dict(kind="begin"))
  File "/usr/lib/python3.8/site-packages/anki/rsbackend.py", line 242, in _db_command
    raise proto_exception_to_native(err)
anki.rsbackend.DBError: DBError { info: "SqliteFailure(Error { code: Unknown, extended_code: 1 }, Some(\"cannot start a transaction within a transaction\"))", kind: Other }

I haven’t been able to replicate this by hammering the y key or double clicking - does it happen without addons?

That would seem to be an issue itself since I just noticed that holding shift on start no longer skips addons for me.

Is there a flag/parameter to do that directly?

edit: Never mind, added one. Error occurs all the same.

No luck reproducing it on another machine either. Can other people trigger this?