I agree that gmail only having offline for certain browsers is suboptimal for the web (though they claim, like amazon with their kindle app, that they will expand support), but it's worth noting that at least the gmail app includes an installable component equivalent to an extension...and there are plenty of single-browser extensions for every browser.
Comments
https://chrome.google.com/webstore/detail/ejidjjhkpiempkbhmp... and https://chrome.google.com/webstore/detail/ejjicmeblgpmajnghn... if you want two most recent examples of Chromium-only applications, where nobody gave a damn whether they follow agreed upon standards.
I agree that gmail only having offline for certain browsers is suboptimal for the web (though they claim, like amazon with their kindle app, that they will expand support), but it's worth noting that at least the gmail app includes an installable component equivalent to an extension...and there are plenty of single-browser extensions for every browser.