Option to remove certain strings

Hi, thanks for the great plugin!

I use it with Bricks Builder and it works great but there is an issue — when I place the video on a website i get:

Your browser does not support the video tag.

in the markdown. I assume reworking parsing engine would be hard and complicated process but what if we could get an option to remove certain strings from the markdown? It could be just the simple input filed to paste the the text we want to remove.

Please let me know what you think about ths idea, I think it could be useful in the similar scenarios where parsed versions get unwanted things from the builders.