Stone Display Bug

For a while now (months?) I have had an intermittent bug where stones occasionally display incorrectly. eg:

This particular stone should be Black and sometimes the bug just adds a couple of miscoloured bars without changing the overall colour like this.

Today I was able to RELIABLY REPRODUCE THE BUG on the HOME page by opening the board display options and clicking on the stone selection that was already selected:

Note that the bug typically occurs on the game page without prompting but I can’t reproduce that.

Environment: PC, Windows 10, Opera (exactly the same result with Google Chrome.)

Game: Play Go at! | OGS (Please don’t comment on ongoing game.)