I like speedscope.app for viewing flamegraphs. It is more interactive than traditional SVG flamegraphs, and what is relevant here is a "sandwich" view - basical

I like speedscope.app for viewing flamegraphs. It is more interactive than traditional SVG flamegraphs, and what is relevant here is a "sandwich" view - basically a sorted list of all functions, you see what function was spent the most time in, click on it and see all calling stack traces like a mini flamegraph, filtered and centered on this function. Speedscope supports several popular trace formats, really useful.