I assume you are talking about the menu items I recently added to the Sourcer popup menu under: Support/Donate... -> Debug...
Those are really just there for debugging so I would ignore them unless there is a bug and I suggest clearing them as a workaround.
The local storage used by Sourcer doesn't just keep growing - there are limits on how much data is cached - just the last page or sometimes the last 30 records used in a census household.
For more information, there are two options:
Clear cached fetch data
Sourcer caches the web page contents returned by a fetch so that, if you bring the menu up twice in a row, it doesn't have to do a fetch(es) the second time. This only applies to a couple of sites where a fetch is need. (Ancestry and FamilySearch mainly). If you clear it won't have any negative effects - just might take a second longer to bring up the next menu.
Clear ALL local storage
This clears all local storage used by the Sourcer Extension. This includes where it remembers certain UI settings. So if you clear it and then bring up the options page it will not remember which tab and subsection you were last on.
This DOES NOT clean the options settings themselves since they are stored in sync storage. You can reset the options to defaults using the hamburger menu on the options page itself.
