There is substantial difference between Magisk v25 and v26, see my post #56297 (earlier on this page):I also thought that /system is now always mounted ro ... but I just tested it on my ASUS Zenfone 8 with OmniROM 13 and Magisk v25.2 in the boot partition
ASUS_I006D:/sdcard/Download # magisk -V 25200 ASUS_I006D:/sdcard/Download # touch /system/bin/testFile_123456789 ASUS_I006D:/sdcard/Download # ls -l /system/bin/testFile_123456789 -rw-r--r-- 1 root root 0 2023-06-07 07:57 /system/bin/testFile_123456789 ASUS_I006D:/sdcard/Download # ASUS_I006D:/sdcard/Download # mount | grep "/system/bin " tmpfs on /system/bin type tmpfs (rw,seclabel,relatime,size=3700224k,nr_inodes=925056) ASUS_I006D:/sdcard/Download #
On v26, you can no more write to /system/(x)bin
And of course, on Magisk v25 and earlier, you write to, Magisk mounts but the mount is lost on next reboot (SAR is not changed/affected)
That is, you can put your changes for /system/bin to a module, service.sh script and Magisk will always mount on the next reboot
But it doesn't work that way in Magisk v26 anymore, since writing to /system/(x)bin will fail (in that service.sh script), hence Magisk will not mount anything there
Oops, sorry - I see you tested with my example from that post, so you did read that post,
Or read-write mount was just something specific to Magisk Delta?