Ok, example. You have 100 files in BRU. You want to change the word to to TO. 9 files will be changed
Currently all 100 will be in the list still and the ones that will be changed are highlighted. This works fine when the list only has a dozen files, but when you have hundreds or thousands in there it can be really hard to find which ones are going to be changed. So adding a tick box that will "Only show files to be changed" or something (prob a better way to word it) would just temporarily hide the other 91 files in the list showing you just the 9 to be changed
I like to change a lot of files at once to have title case (AKA First Letter Of Every Word Capitilised) but this also changes things that should be in all caps (such as AKA or NASA) and so you wanna make sure they don't get caught in the mass change. It's not easy when your list has hundreds of files