TargetTalk

I was adjusting my trigger and doing a little bit of cleaning too, when suddenly this piece appears out of nowhere.
Where could it could it be from? Is it safe to use the gun without it, the dry fire at least seems to be working as it should, but I don't want to risk a further damage.

Please use https://imgbb.com/ to host pictures. Photoshop charges to view

Ok, done that.
Haven't used photobucket in years, I quess it's time to remove my account from there, since it jut keeps getting worse.

Its the broken tail of the spring No. 190 Part 2744308 which fits on the sear catch No. 16