Note to Dev: People can't redirect apostrophes, utm_source stuff, etc. These important needs are not being addressed.
You don't necessarily have to come up with a solution (it may be tough), but some more guidance would be helpful since you are the expert here. For example, it would be more helpful if you said "I'm not sure, but I don't think it can be done" than no response at all.
I need to find some way to redirect URLs containing "+".
For example: /?s=driverless+cars
You may recognize the above as the URL format for search results inside WordPress. I'm trying to get the most searched-for keywords to automatically redirect to specific pages/posts.
(No, I haven't found a plugin made for this... so your 301 redirect is my last hope.)
Dev: if you can't create the functionality to allow "+" and other symbols in URLs, can you at least say why? Maybe we can find another solution.