On the phones, where the Vendor kernel has this option enabled, Lineage also enables it, e.g. most LGs.

But Lineage does not enable it on all kernels, even if it could just be enabled. I observe this on all of my Samsungs, for example.

You can use this app to see which USB gadget options are enabled on your kernel: https://github.com/tejado/android-usb-gadget

Makes sense. My phone model is a Xiaomi. Don't know why Samsung would ship their kernels without ConfigFS support but I have never had such issues.

It's not about `ConfigFS` as a whole, but specifically `CONFIG_USB_CONFIGFS_MASS_STORAGE`, that is left disabled, while lots of other `CONFIG_USB_CONFIGFS_BLA` are enabled.

This and more can be seen in the `device info` screen of the App mentioned above

Should have said *proper ConfigFS support. Anyway, had no prior interest in this kernel feature until you mentioned the anomaly that is specific to certain vendors.

You can also do `zcat /proc/config.gz | grep CONFIGFS_` in a root shell (su) inside termux to get what options are set by the default kernel.