I flashed OpenWRT 22.x from their repository and then decided I wanted to go back to OEM. Since OpenWRT does not undertand the GL-iNet images, I powered into the bootloader by holding down reset and flashed the 3.100 firmware that way but it did not revive the router completely.
Thanks, I had already seen the support page is stating the latest stable version for the MT300N-V1 is 2.265.
However, in his post above, @alzhao seems to contradict this as he appears to state that the OP should use v3.216 on his MT300N-V1.
My question is whether @alzhao mis-spoke because maybe he thought the OP was asking about an MT300N-V2, or whether the V1 does indeed work with 3.216 and the support page for the V1 model is outdated.