What I often do is I will upload a full event video to Youtube, and set it to non-listed but that anyone with the link can view it. Then I just copy the youtube link into the forum post and it works the same except that there are no size or length or resolution limitations and it’s less work than cropping and trimming and scaling a video to fit in the tiny limit and still totally free and lets me maintain control over the video too. Works pretty good. You should consider it.
It’s really simple to do, just click on the camera with the plus sign, then Upload Video
Then just upload it
And on the Visibility question I just set it to unlisted
Then copy the link it gives you for it into here.
Then everyone here can see it, but it doesn’t randomly show it to random people on youtube.
That might save you some headache.