You
Web font swaps cause a visible reflow. Fix?
ChatGPT
font-display: swap plus a fallback stack with matched metrics. The modern lever is size-adjust and ascent-override on the fallback @font-face, which lets the substitute occupy the same space, so the swap becomes invisible rather than merely fast.
You
Why does my page jump while images load?
ChatGPT
Because the browser does not know their size until the bytes arrive. Set width and height attributes, or an aspect-ratio in CSS, and the space is reserved from the first layout pass.
You
How do I know when it stops being worth it?
ChatGPT
When you stop noticing it. If it has not surfaced a problem in six months, it is either solved or it was never the bottleneck you thought.