I think starting from Oreo custom kernels for our device started modifying /system due to things oneplus changed, flashing a kernel is often no longer limited to the boot partition, so if you flash a certain kernel that modifies the system partition and then switch to another kernel it might create a mess, cleanest way is to revert changes previously done to /system first by dirty flashing the ROM before switching to another kernel - it's not that you're going to damage your device if you ignore/forget doing this but you might experience issues/bugs due to this, I think people often reported broken Wi-Fi and stuff like that... and I read the suggestion on various places, engstk was the first one I remember!The instructions state that you should dirty flash stock ROM if your on a custom kernel. it's the first time seen that recommendation when flashing a new kernel.
Is there a specific reason for this, and if so what would be the repercussions of not flashing the stock ROM prior to flashing your kernel? Not a big deal, just curious. Has anyone tried just flashing the kernel, then wiping the cache and dalvik just to see if it's necessary?
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