yep.
I could write a book about all of the stuff I have found in a "clean" fuel tank.
Plant matter is the worst because it sort of 1/2 floats so when the mower is running it gets sucked into the outlet and forms a plug, much like hair in the shower drain.
Then when you stop, they break up and float off
So you get the starving after an hours or so then works perfectly, then starves then works perfectly thing cycling over & over again.