This is a good question. On the one hand, the article says: > Of all the work needed to support the new hardware, porting Firefox to the 64-bit ARM architectur

This is a good question. On the one hand, the article says: > Of all the work needed to support the new hardware, porting Firefox to the 64-bit ARM architecture was not actually something we needed to do: we’ve supported 64-bit ARM on Android and Linux for years. On the other hand, it says: > Secondly, we needed to adapt and fix the various parts of the Firefox codebase that deal with low-level calling conventions and particularly the interfaces between the JavaScript and C++ (and nowadays Rust) parts of the code. I suppose MacOS on ARM has a different calling convention to both MacOS on x86-64 and Linux or Windows on ARM64. Also: > If the user visits such a site, Firefox will automatically download and install such a proprietary EME/CDM module. This presented a problem to us as we would be dependent on those third-party vendors to publish ARM64 versions of those decoders. So what do Windows or Linux users on ARM64 do? Do they just not get DRM?