When I go to use the keyboard shortcut for "Find action" (command+shift+A), macOS opens the terminal and with some output: myPreviousSearchResult\;type\=a,(replace myPreviousSearchResult with the previous search result you did on in the search bar).
It doesn't happen all the time, which adds to the peculiarity, and often does not happen when I first launch the search bar. Only the second search and onwards.
Here is an example:
Answering my own question because finding the notice took me too long and was quite frustrating. I considered glitchy IDE plugins, other apps installed, and searched the web for all sorts of terms. I didn't consider the OS was adding shortcuts for random things like this.
You need to disable a keyboard shortcut in System Preferences > Keyboards > Shortcuts > Services > Text (dropdown menu) > Search man Page Index in Terminal.
If anyone has suggestions on debugging keyboard shortcuts (finding out which apps are handling them), please let me know.
