I don’t believe that they’re outright banned, but rather held to a higher level of scrutiny because many could be considered short/trivial.

I’m heavily involved in many flash game communities (Learn to Fly, Duck Life, and others). As long as the game is substantial enough to warrant speedrunning it should be fine.

That being said, You Have to Burn the Rope is a rather popular speedgame where the only category is under 30 seconds long.

@Caarda You Have to Burn the Rope was added to the site over five years ago and likely would not be approved under the current rules.

That is very true, under the current rules i dont even think the humongous games would make it onto the site.

There's a fair number of flash games that have been added fairly recently. As an example, check out Oreo321's repertoire.

Flash games aren't banned, but they're less likely to be accepted.