(Credits go to Knoxville and others from Telegram for this method)
For remounting, we need to use the alt-f1 console or built in terminal.
For Bliss 15.x: Boot with DEBUG=1, and mount remount the install partition:
mount -o remount,rw /dev/block/sd(x)
cd /src
mount system.sfs /tmp
cp /tmp/system.img system.img
umount /tmp
rm -f system.sfs
or if you want to backup original system image
mv system.sfs system.bak
Now we sync the filesystem and reboot:
sync
reboot -f
Upon reboot, you will have R/W on system
Once we have a system.img and no system.sfs, we need to use the built in terminal app (with su permissions granted), and type:
cat /proc/mounts
Then look for the /dev/loop# where we see mounted at "/", likely followed by "ext4 ro....". Note that as we will need to use that for the next command.
Now type:
mount -o remount,rw -t ext4 /dev/loop# /
Or for older Bliss versions (14.x, 11.x) use:
mount -o remount,rw -t ext4 /dev/loop# /system
Then you can edit the system files you need. When you are done, you can remount as RO:
mount -o remount,ro -t ext4 /dev/loop# /
Then test to verify changes stick
Video Walkthrough Watch this video for detailed instructions.