I recently bought a new RG35XXSP, as my old one was on its last legs.
Upon installing the latest muOS Jacaranda (as the Pixie version I used on my old unit would not boot), I quickly discovered that the display would, after a while, display irremovable horizontal lines on the bottom of the screen.
I went to look for a fix, and I found one called “FexFlasher”.
Here is the link to that fix: GitHub - andromalandro/FexFlasher: Windows tool to flash .fex file to sd card, intended to fix muOS screen issue (horizontal lines), this was made for the 35XX PLUs and H devices, it changes some screen timings and it may break your muOS installation or damage your screen, back up your SD card and use at your own risk. · GitHub
Following these steps did fix the horizontal lines on the screen. However, my RG35XXSP refuses to go to sleep with the fix applied. When I close the lid now, nothing happens at all.
I looked everywhere and I cannot find the same fix fit for the RG35XXSP; only the one that was meant for the 35XXH that does fix the display issue, but breaks sleep on the RG35XXSP.
I absolutely adore muOS, I’ve used it every single day for the past 2 years and found only it handles all of my sometimes very specific use cases, like being able to read large EPUB formatted manga. In other words, I really don’t want to switch to another CFW.
Could the devs, or somebody else, provide me with a fix for the horizontal lines that doesn’t break the sleep function on the RG35XXSP? I would be very grateful.
Thanks for listening 
EDIT: I fixed the issue myself by creating a custom boot_package.fex and changing the values to the ones from this post and applying that to a stock muOS RG35XXSP: Definitive fix for the Horizontal lines bug - RG35XX Plus
As not everybody is willing to break their head over this inside linux for 3 days, I applied the custom boot_package.fex to a fixed RG35XXSP install image, and i will post the download link to it here soon if that is allowed.
Greetings
Download link to the FIX: https://drive.google.com/drive/folders/1feBvjB9zF49S6m4KftjipV2sF1Zhc-\_E?usp=sharing
muos-RG35XXSP-fixed.zip contains a ready to go install image of muOS Jacaranda with the rg35xxsp fix applied.
boot_package.zip contains the fix that was applied to the fixed image. you could use it to flash your existing SD-card but, if you do so, do it at your own risk.
This is not an official fix, I tested it on my new RG35XXSP unit with the revised screen and it seems to have fixed all the issues it had. Only install this if your RG35XXSP suffers from the horizontal lines on the official muos image and, if it does, once again install it at your own risk. Having your screen run on bad timings can potentially damage your screen so be careful.
Good riddance!
Please be aware that installing any third party modifications, patches, scripts, packages, or altered MustardOS components is done entirely at your own risk!
These modifications are not developed, reviewed, tested, endorsed, or supported by the MustardOS project or the MustardOS development team, unless we have explicitly stated otherwise.
Third party modifications may change system files, configurations, services, permissions, boot behaviour, emulator settings, or other components in ways that differ from an official MustardOS installation. This may result in unexpected behaviour, instability, data loss, failed updates, degraded performance, broken functionality, or, in some circumstances, a device that no longer boots correctly.
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