SwiftKey for Android capitalization
Microsoft SwiftKey has an issue with Android, that ignores HTML attributes for autocapitalization.
I filed a bug with the Google Chrome team here https://bugs.chromium.org/p/chromium/issues/detail?id=1092224#c13
It's their suggestion that having tried multiple keyboards which do work, this is a bug in Microsoft SwiftKey.
I can confirm I have now switched my device back to the Google Keyboard which works as intended with modern HTML, but you may want to have capitalization work on a broader remit, than that of a toggle switch.