I think there are more important tasks to do but perhaps somebody from developer team will comment it better.
Perhaps better decoding of VC-1 in future could be a side effect - AFAIK the video drivers on RPi 4B are not yet finished in general and it's still in progress. But it's hard to say how long it could take.
Thanks for a comment. I still don't understand why Kodi shows such an unusually high value of free memory.
It was always strange but as soon as I have created a tmpfs filesystem in RAM which is now occupied by about 800 MB of Timeshift buffer data, the Kodi's report regarding to Free memory is now absolutely nonsense on my RPi 4B / 2GB RAM.
That's why I am asking if developers (who can better than me understand how things work) are considering it as OK... Maybe it's not just a GUI info message - if the same value is used somewhere in Kodi's background, it could perhaps sometimes lead to memory overflow etc (and the oom killer sometimes appears...)...
FYI the current values:
Kodi Free memory: 1424MB
top - 10:39:55 up 17:22, 3 users, load average: 1.26, 1.43, 1.45
Tasks: 148 total, 1 running, 147 sleeping, 0 stopped, 0 zombie
%Cpu(s): 8.6 us, 3.5 sy, 0.1 ni, 87.3 id, 0.0 wa, 0.0 hi, 0.5 si, 0.0 st
MiB Mem : 1863.3 total, 386.9 free, 438.9 used, 1037.5 buff/cache
MiB Swap: 0.0 total, 0.0 free, 0.0 used. 529.9 avail Mem
# cat /proc/meminfo
MemTotal: 1908012 kB
MemFree: 395616 kB
MemAvailable: 542032 kB
Buffers: 45152 kB
Cached: 990108 kB
SwapCached: 0 kB
Active: 791468 kB
Inactive: 486616 kB
Active(anon): 634920 kB
Inactive(anon): 405900 kB
Active(file): 156548 kB
Inactive(file): 80716 kB
Unevictable: 45036 kB
Mlocked: 0 kB
HighTotal: 1231872 kB
HighFree: 30896 kB
LowTotal: 676140 kB
LowFree: 364720 kB
SwapTotal: 0 kB
SwapFree: 0 kB
Dirty: 0 kB
Writeback: 0 kB
AnonPages: 288024 kB
Mapped: 108004 kB
Shmem: 797996 kB
KReclaimable: 27780 kB
Slab: 59440 kB
SReclaimable: 27780 kB
SUnreclaim: 31660 kB
KernelStack: 1888 kB
PageTables: 3128 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
WritebackTmp: 0 kB
CommitLimit: 954004 kB
Committed_AS: 1548760 kB
VmallocTotal: 245760 kB
VmallocUsed: 12216 kB
VmallocChunk: 0 kB
Percpu: 512 kB
CmaTotal: 524288 kB
CmaFree: 320136 kB
As there's no feedback or comment from developers and it seems the Timeshift issue is more worse than better in latest LE 10 Nightly on my RPi / 2GB, I decided to try a different Timeshift configuration.
As I had no idea what's happening in memory with Timeshift data / how it works, I created a tmpfs mount and instead of RAM Only, I changed the Timeshift configuration in Tvheadend backend to use /tmp/ramdisk with 800 MB size and currently I am testing how this works... At least I can see how the buffer files are created and when are discarded.
So far it looks that Kodi is sometimes loosing a pointer in Timeshift data (and gets messed) even in this configuration but the Plus is the files are not discarded immediately when this happens. But it's too early to say that's fact - it needs more thorough testing in my environment.
Nobody commented it so far but I would like to know if it's really OK how the Free memory in Kodi is reported?
It's still the same in latest LE 10 Nightly and to me it looks confusing.
For instance:
1)
Kodi - System info - Summary
Free memory: 1360MB
top in SSH console:
top - 21:29:55 up 4:12, 1 user, load average: 1.17, 1.36, 1.42
Tasks: 144 total, 1 running, 143 sleeping, 0 stopped, 0 zombie
%Cpu(s): 9.2 us, 4.1 sy, 0.3 ni, 85.3 id, 0.0 wa, 0.0 hi, 1.1 si, 0.0 st
MiB Mem : 1863.3 total, 462.7 free, 503.5 used, 897.0 buff/cache
MiB Swap: 0.0 total, 0.0 free, 0.0 used. 614.3 avail Mem
2)
Kodi - System info - Summary
Free memory: 1303MB
top in SSH console:
top - 22:32:01 up 5:14, 3 users, load average: 1.44, 1.38, 1.39
Tasks: 148 total, 1 running, 147 sleeping, 0 stopped, 0 zombie
%Cpu(s): 6.9 us, 4.0 sy, 0.3 ni, 87.7 id, 0.0 wa, 0.0 hi, 1.1 si, 0.0 st
MiB Mem : 1863.3 total, 225.1 free, 553.4 used, 1084.8 buff/cache
MiB Swap: 0.0 total, 0.0 free, 0.0 used. 348.5 avail Mem
The best current solution is perhaps to transcode these few movies to HEVC (if it's <= 4K@30 Hz). Or wait until there's a driver improvement regarding to VC-1 decoding.
Well, I thought this question was about a backup of further working / fresh LE installation as from my point of view it's too late to try backup a corrupted installation and .kodi folder might not be enough.
By using a search, you may find something like this: Basic backup/restore question
But how can i preserve all my settings, add-ons, media db? Should i backup .kodi folder for that?
There's a backup option in Kodi - see menu Settings - LibreELEC - System - Backup
Klojum OK, you are right - my fault, sorry, I have overlooked it... 
It looks, for some unknown reason, I have focused more to your post #2 and "4 devices" mentioned than to original subject... 
Yeah the .json file is not there at the moment but the Nightly builds are generated so you may still update manually through SSH console.
It's also important to keep the bootloader updated as there're several fixes regarding to SD card.
rpi-eeprom/release-notes.md at master · raspberrypi/rpi-eeprom · GitHub
There's an example how to easily upgrade the bootloader to latest one:
RE: Is it possible already to set up a rpi4 with kernel 5.4?
Also make sure you don't use any suspicious / banned add-ons which seems to be the quite often reason of such issues.
See here: Official:Forum rules/Banned add-ons - Official Kodi Wiki
Edit - Arghh, sorry - I have overlooked it's RPi 2B so my post is a bit irrelevant regarding to bootloader update (which is valid for RPi 4B)... 
I have installed easybcd on the disk where windows 8.1 is and I have given an option and it has eliminated the windows boot, how can I recover it?
This should be enough:
fdisk /mbr
You'll just need a bootable media with FDISK, for instance: https://www.techwalla.com/articles/how-t…table-usb-fdisk
Attach a USB keyboard. Press the PrtScr button, and find the screenshots folder in the LibreELEC storage.
Unfortunately this does not work on LE 9.80 / 9.95 / 10 Nightly anymore - only Kodi menu can be saved currently. Perhaps in future this will be supported again.
Well, the path is a bit different but here it is:
Click the Shift button and you should see the top row changed so the @ character is there instead of 2 .
I have to confirm this issue after more intensive testing through several past days and it is really a nightmare.
It does not matter which Tvheadend backend is used, the same issue happens on both 4.2 and 4.3 Alpha, quite often during seek operations but randomly. The same issue on 2 different RPi 4B devices (2 GB, 1 GB), latest several LE 10 Nightly builds (currently 20210321).
So far I was not able to reproduce it with any specific tasks that I could describe but it seems to be related to this common error message in the log:
LibreELEC tvheadend[1677]: htsp: 127.0.0.1 [ | Kodi Media Center ]: Disconnected
In the same second it's reconnected again but the Timeshift data are lost.
If I am not mistaken, this means the Tvheadend client (8.2.3.1) is losing the connection to Tvheadend backend so the itself Client could be the reason of the issue? I have tried to increase the Connection / Response timeouts from defaults 10 / 5s to 20 / 15s but it did not help.
CEC doesn't come back until I reboot
As Kodi is detecting the HDMI devices at start, perhaps just restarting Kodi should be enough instead of rebooting whole LibreELEC:
systemctl restart kodi
As a temporary workaround I would then map this command to some unused IR Remote key.
