Remove (too many) spaces and a question about active extensions

Two questions.
When editing text, a common, repetitive operation is to remove two or even more spaces (mistakenly created while typing), where there should be only one. Is there a possible variant of the Remove Spaces extension that does this job? Would be great!
Quite apart from this, I would like to ask members of this forum how they deal with the problem of too many active extensions. They are all so terribly useful that the list becomes too long to be practical. Choosing is hard…