v21.2 is a maintenance update, mostly addressing bugs, and expanding device compatibility. Checkout the full v21.0 release notes if coming from older releases.

v21.2

• [MagiskInit] Detect 2SI after mounting system_root on legacy SAR devices
• [General] Make sure post-fs-data scripts cannot block more than 35 seconds
• [General] Fix the magisk --install-module command
• [General] Trim Windows newline when reading files
• [General] Directly log to file to prevent logcat weirdness
• [MagiskBoot] Fix header dump/load for header v3 images

Full Changelog: here