Profiling in VSCode returns some red bars with "Flag: GC" - what do they mean?

You commented the perfect time, was just testing something. Basically using TimerOutputs package I am tracking each function - I think there is a bug in the package somewhere, since I see a low number of allocs for functions when BenchmarkTools would say zero. But back on track the function updatexᵢⱼ! returns 0 allocs:

But I get the GC flag for this function and two others as well;

And I just don’t know why.

Kind regards