Thank you for reaching out with your bug report!
You can see the problem in the extlinux.conf you pasted above. This is the problem we diagnosed here two weeks ago: Ptyxis high CPU utilization
It will be fixed in the next release of reform-tools. Sorry for the mess. If you cannot wait, you could manually edit /etc/u-boot-menu/conf.d/reform.conf and make sure it contains the following and then re-run sudo u-boot-update.
U_BOOT_FDT_DIR="/dtbs/"
U_BOOT_FDT="/freescale/imx8mq-mnt-reform2.dtb"
What I don’t understand is how this problem only shows up now because reform-display-config had this bug since 2024.
I should add a check for this to reform-check.