Filters for in game group threads
Interesting ...
Yup, confirmed the bug - and I think I've found the cause: the Change link should be adding a negative sign before the group name in the address line, but it isn't - eg should be &filter=-A at the end, not &filter=A.
Probably easier to remove then redo the filter (as you say) than to manually edit the address line after clicking on the Change link to add the negative sign then refreshing the page.
I believe all his development work is now focused on the responsive site, with a view to eventually retiring the old site so I don't know that jase will be fixing this bug, particularly as there is a workaround ... but even so thanks for bringing the issue up. :>