Chat bookmarks can only be created once every 30 seconds.
If you attempt to create a conversation bookmark in chat, but a bookmark with that name already exists, you will get an error message but you'll also have to wait another 30 seconds.
The throttle timer probably shouldn't run if an error occurs.
In my case I ran into this with the unfortunate sequence of events:
- Make a bookmark named "GitHub Issue #3"
- Missed a few messages, decided to make another, typed same name, received error, wait 30 seconds.
- Tried "GitHub Issue 3", surprised to find out that it considered that name to already exist too, received error, wait 30 second.
- Ended up naming it "the problem". Took 60 seconds total.