Some news:
- my laptop now "smoothly"(?) boots (again, it already did but stopped for a while eventhough I haven't changed anything relevant in my BIOS) Manjaro Linux KDE 20.1.2 (default kernel)
- thanks to the article linked by captain-sensible I now can show/hide the hidden setting/s of the "Main" menu of my BIOS(Acer InsydeH20) by CTRL+S
- in the latest available version of the BIOS the only hidden option is a toggle for the touchpad PS2/I2C interface
- I've tested the two "ivrs_ioapic" boot parameters with and without the noapic boot parameter and the noapic boot parameter alone too, they all didn't affect the boot at all, but they neither fixed the freeze I'm encountering with calamares(manjaro installer) and KDE Partition Manager (both partitioning-related issues)
I mention this "new" issue cause the freeze happens about 30s after I start any of these programs, which is as much as it takes for the LVM2 monitoring start job to freeze the laptop at boot.
As you may have already guessed I hypothesize either the start job is now just postponed either the start randomly can trigger the same freeze which KDE Partition Manager/Calamares can trigger at 100%.
Unfortunately I've no important experience with reading linux logs, would journalctl or dmesg be useful?
Apart from this,
@Duxi have you already updated your BIOS to
the latest version? Have you tried o boot with "Fast Boot" and "Secure Boot" disabled?
Eventhough I'm recommending you to do it I have to report the "Fast Boot" option never afflicted the boot of Manjaro by a Live USB, and the "Secure Boot" can be left enabled as long as you manually add the "efi\boot\bootx64.efi" in the list of the trusted EFI executables by the "Security" menu of the BIOS.