Reviving this old thread because a fellow in discord had the same issue mentioned here, and managed to fix it by disabling something called 'Windows Aero'. Not sure if this solution will work for everyone else, but maybe it will help, and at least is a hint that other windows processes could be the culprit.

Just wanted to say I'm in favor of creating a new category for just All Hearts without having to complete every level, and I'm even in favor of it becoming the 'main' all hearts category, just because I think it differentiates all hearts from 100% in a pretty interesting way.

The first 4 hearts are widely agreed on to be the fastest to get. Pretty easy to remember :)

I believe that run was submitted before the rule was put in place. The reason for the rule is that 1.2.3.0 allowed you to perform a wallbounce off of spiked walls, an oversight which was quickly patched out. Since buhbai didn't use that trick his run was allowed to stand.

Celeste is the game that got me into speedrunning: https://www.speedrun.com/Celeste . Casual and speedruns both are very fun. Speedrunning looks and feels amazing. Very active and populous community (currently #1 most active on this site).

Here's a vid of the current world record:

Checkout Celeste: https://speedrun.com/Celeste

It's an incredibly fun speedrun and it matches all of your requirements :D