Hey there!
Long time user, first time reporter. I got a new laptop recently and updated my theme to match. I noticed that for whatever reason, when typing into this theme, there was some input lag. That's weird, since I've never experienced that with any other theme. Just to verify, I swapped back to some defaults and other themes I made. Nothing else exhibited the same behavior.
The theme is here: https://www.dropbox.com/s/5t1bvxv5glcn1ph/laggy_theme.alfredappearance?dl=0
I've attached my system specs (there's an AMD graphics card not shown). I'm using Alfred v3.4 [850], the most recent one.
I realize this isn't the most helpful bug report to reproduce, so i'm happy to supply any other information you need.
Thanks a bunch!