I had the same issue here and i fought it for months.
My issue, more specifically, was pressure from my thumb on the left side decocker was slightly twisting the frame just enough to cause the trigger bar to bind. But previously it did it without that pressure too.
Here's my post below explaining what fixed it for me.
Here's my video of my version of your issue as well
https://youtu.be/GKpB_eEURgE the comments are hilarious as the 12 year olds tell me i am just "doing it wrong". regardless, i was getting the exact same symptoms your video shows. Totally free trigger after live or dry fire then eventually it'd catch.
I hope this helps, drove me absolutely bonkers trying to fix it. I love my P07 now and it's my primary 9 for suppressor use since the fix.
I sanded a bit in the area below on my trigger bar and i have put hundreds of flawless rounds through it since. 100% fixed.
I was able to reproduce the issue with the slide off too. The trigger bar had lateral movement left to right of the frame as you pull it. While hard to see the red area below was where mine was binding. It was hugging the right side of the frame until it'd catch and click over to the left side, then catch the disco and be back in business. Check if you can reproduce it with the slide off. If it stays to the frame side nudge it to the left a tad and see if it'll catch.
little update for my dead trigger issue...
Took the whole sear cage out and apart a few more times and still got dead triggers a few times out of 100 or so dry fires. Too many for me to call dependable.
I was about to order a new trigger bar and a few other parts and decided to try it out one last time with the decocker out and safety in place.
Completely resolved the issue. So a bandaid, as i lost decocker function, but i am fine with that in my situation.
Got a few hundred dryfires so far with not a single dead trigger, will post back here and edit this if i do.
Just dropping this here for anyone else who has this issue. One solution that worked in my case.
Two week update:
So, I hit the range and put a couple hundred rounds through it and the issue came back. Even with the safety installed.
Ordered the cgw omega trigger. Will see if that resolves it.
A few weeks later, yes, the omega trigger from CGW did, in fact, fix the issue 100%. Not a single dead trigger since install.
Later update. I finally was able to track down the issue and it's twofold. First, my grip is pretty firm, Weak hand really clamps down and i was pressing my strong hand thumb into the decocker with my weak hand thumb. With the slide off, gripping as i would in rapid fire (tight grip) i was able to visibly squeezing the polymer of the frame around the rear frame insert. This squeeze was pushing the trigger bar ever so slightly toward the left side of the gun. If i used a weak grip or one handed, i was never able to duplicate the problem. As soon as i clench down on the pistol (as you would for USPSA or any other rapid fire) the dead trigger would come back.
I bought an ebay slightly used trigger bar in hopes that wherever it was contacting might be different from the one I was using.
Same dead trigger same issue. So I took the slide off and watched the trigger bar carefully while manipulating the trigger. I saw that it was sticking against something hidden by the sear.
Experimenting, since i had an extra trigger bar on hand, i sanded the vertical surface i shaded red in the pic below. I used 400 grit and went slow, taking off only a tiny bit. Reassembled and the issue went almost completely away, but if i gripped really hard i could make it do it still. I proceeded to sand a bit more and the issue completely went away.
Since then, i've put at least 500 more rounds through it and have yet to produce a single dead trigger. Stronger grip, weaker grip, dirty, clean, zero issues now.