cant help, but i essentially asked the exact same thing yesterday.
linking that ticket for reference.
https://community.zammad.org/t/filtering-of-html/5933/5
Im hoping to wind it out to say 60 seconds or so.
I dont think there will be any negative repercussions from it, other than an email taking longer to get processed and show up in the system. which is not a big deal for us.