How to make categories appear as a dropdown list

If I am not mistaken, one of the previous versions of wp had the option of converting the list of categories on the main page into the dropdown list out of a box (i.e. turn <ul><li> into <select><option> etc.) – now I managed to do it only with the archives, but I did not find such an option for the categories, and I would like to, as I have multiple categories on by site and they started to get a good part of the page.

Did not find it in the support forum or among the plugins.