I know at least Preview on MacOS has this feature now: if you try to put a black bar over text it tells you this isn’t secure and offers to redact for you using

I know at least Preview on MacOS has this feature now: if you try to put a black bar over text it tells you this isn’t secure and offers to redact for you using a method that both visually replaces all characters and removes the embedded text underneath It is non-destructive until saved meaning you have a window in which to make changes before the data is gone.