Here's where I'm seeing the "long task" in Chrome. I'm not as familiar with their performance tools, but I think (?) this is roughly equivalent to a red jank bar in the Firefox profiler.
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Here's where I'm seeing the "long task" in Chrome (notice the tooltip from me hovering that red shaded area). I'm not as familiar with their performance tools, but I think (?) this is roughly equivalent to a red jank bar in the Firefox profiler.