iirc Adobe has dropped NPAPI support for browsers on Linux, leaving Chrome on Linux as the only browser that support the new PPAPI interface.

So if you want to use new versions of Flash on Linux, you have to use Chrome.

Obviously Chromium supports PPAPI too, but as far as I can tell the PPAPI version of Flash isn't available for it so the official Google-branded Chrome releases really are the only option for Flash on Linux.

The only option to get newer versions of the Adobe plugin. The 11.2 branch will get security updates into 2017 (2012-03-27 + 5 years): https://blogs.adobe.com/flashplayer/2012/02/adobe-and-google...

You can use the PPAPI versions with Chromium if you want to. You just need to extract the so file from chrome package and use it for Chromium. There are readymade packages available in AUR for instance. Of course your point stands that officially Chrome is the only option left.