There is a prefers-reduced-data media query draft [1] which addresses the issue. It doesn't actually check the bandwidth, though (although I believe there are o

There is a prefers-reduced-data media query draft [1] which addresses the issue. It doesn't actually check the bandwidth, though (although I believe there are options to put a mobile phone into "reduced data" mode below a certain bandwidth). [1] https://developer.mozilla.org/en-US/docs/Web/CSS/@media/prefers-reduced-data https://developer.mozilla.org/en-US/docs/Web/CSS/@media/pref...