- HTML can be streamed and rendered ad-hoc in the browser. - If you don't stream HTML directly, you can use the streaming API (browser native). - If you use o

- HTML can be streamed and rendered ad-hoc in the browser. - If you don't stream HTML directly, you can use the streaming API (browser native). - If you use one of the above techniques you can show a progress bar on top of it. - Alternatively count the things you fetch and drive a progress bar out of that. - If you have a single request and one big thing you fetch (typical for backend for frontend pattern) then you might roughly know how long it should take. - You can add some currently known quantity to your heuristic to determine estimates. - You can alert the user with "takes longer than expected" messages and clearly communicate the implications of a reload.