What fixed it for me was disabling in game overlay and putting "C:\Program Files (x86)\Steam\steam.exe" -no-browser in my Run window and that completely killed any "Steam Client Webhelper" instances in my task manager. I'm pretty sure that they were my steam chats, as anytime someone messaged me on steam and the window popped up, I'd get fps drops and another "Steam Client Webhelper" would appear in my task manager. Doing the -no browser thing turned all my steam chats into the dated looking chat windows:
https://cdn.discordapp.com/attachments/264711155098976256/844650569590636544/unknown.png
https://cdn.discordapp.com/attachments/264711155098976256/844650791797129256/unknown.png
which I assume is what fixed it.