On a recent project I realised I needed some kind of marker to appear when a particular filter was in use. The dashboard had quite a few filters and it was easy to forget which ones had selections made.
Note: this only works with single value filters.
I know it seems a bit hacky and fiddly, but once you've nailed it, it's a great tool to have!
I've attached a workbook so you can see how it works.
Link here > Tableau Public
(tried to embed but filters didn't work)
Thank you for sharing Caroline.