If ‘save into document=true’ in the advanced settings, no highlight can be undone once it is saved. If ‘save into document=false’, the information related to the location of the highlights is saved into a separate file which can be modified. There are two different ways of erasing highlights in this case as far as I know:
- Find the exact entry in the newly created file associated with the location of the highlight and erase it; this can be ridiculous if you’ve done a lot of highlights already.
- If the highlights were done by text highlight (not area highlight done by ‘ctrl+mouse+h’), then reapplying the highlight to the exact space will undo it. The color should be matched in this case. This method can be used even if ‘save into document=true’ IF the highlights are not saved yet.
I don’t now any simple way of removing area highlights other than searching the whole text file See the previous thread for more information.