This is actually great. I ran into this problem recently. I wanted to push out some CSS while waiting for some external response. Unfortunately, it was very imp

This is actually great. I ran into this problem recently. I wanted to push out some CSS while waiting for some external response. Unfortunately, it was very important to be able to send a 404 in case it turned out the external response. This means we had to live with a higher TFFB. Let’s hope this becomes widely adopted soon. Does anyone know how long it took till other HTTP features that were added later (not HTTP2) were widely supported?