Tags
@anon41602260 posted a nice idea that tags can be dragged into the dock and open in grid, fan, etc. of your choice.
This is something I need to do myself. Especially with all the creative names developers come up with.
Plot twist: the tags apparently have to be in the side bar, so you can click All Tags… to see all the tags, then drag your desired tag to the side bar and release. From there you can drag it into the Dock.
Plot twist 2: At least one Apple app (Notes) doesn’t allow tags to be added. (of course)
Hm. Pretty cool just having the tags in the sidebar. You can click to see e.g. notes apps, or drag and drop an app on the notes tag to tag it.