Hi, I have a TP-Link Archer D50 v1 and I’ve read through a lot of pages and what I understood is that I have to use U-Boot with serial recovery method to upload the firmware image and install it. My question is: Can I make a custom image which I can use to upload and install the firmware from the default webui of the router without it refusing the image? If not, Is there anyway to install OpenWRT without opening the router and connecting the UART converter to it? (It seems that my router doesn’t boot in recovery mode whatever I do but also I’m having difficultied opening the case of my router). Thanks for your patience and any info is much appreciated!
possibly, it's for you to find out by reverse engineering the stock firmware.
you think OpenWRT only posts the most cumbersome installation method available out there, to piss people off ? 
keep in mind DSL modem doesn't work in OpenwWRT, and the device is highly discouraged due to insufficient flash and RAM - https://openwrt.org/supported_devices/864_warning.
Can you tell me how to do it? I have a stock firmware image but I don’t know what software to use and what to look for.
Yeah I know that, thanks for the headsup tho. I don’t need the DSL modem as I intend to use it only as a router.
for the flash problem, I intend to use a USB stick to increase the storage room. It’s possible, right?
Thanks for the complete answer
Binwalk, as for what to look for, neither do we.
You could also try to get cli access, to see what happens when the firmware is uploaded through the stock webUI.
You would however save a lot of time by simply switching to serial.
I’ll definetly buy a J2 UART connector to do the process. Thanks for the info!
Any idea on whether the USB trick will work?
Is there a detailed guide on how to setup the UART connector regarding physical connections?
You can find everything you need on YouTube.
Then there's TP Archer D50, bootloader issues (please add debrick to wiki) - #13 by Forelle.
As noted in that thread, make sure you connect to the correct serial port, your device got two.