Hello, sorry for the problem, and strange that you cannot even uninstall it, that would suggest a Firefox problem maybe.

Would you mind opening an issue on https://github.com/aaFn/Bookmark-search-plus-2/issues, with a screenshot of the Firefox Add-ons page, and also indicating to me which version of Firefox this is, on which OS ?

Also, could I ask you to go to the Options page of the add-on, activate the Traces option, and then would you agree applying this procedure https://github.com/aaFn/Bookmark-search-plus-2/wiki#debugging-bsp2--reporting-errors and report me the errors or messages that you see ?

Thank you in advance, and again sorry for the inconvenience, aaFn.