Hey I've been trying to scan the generated QR codes but they don't seem valid, I tested with 2 differents apps on my phone (the most downloaded and highly ranked on Google Play store), and none of them worked. I installed another addon, WOWQR that can generate QR codes containing the url to the Warhead Classic page about your target and this one works. I've done a file compare of the QR encode library file your addon and the one that works and there are differences, perhpas you that can help you solve the issue.

nothing to do with the client
tested with iphone camera, both of them work

maybe the cause is the background is not transparent and should be high contract to the image

changing f:SetBackdropColor(0,0,0); to f:SetBackdropColor(1, 1, 1); in CreateQRTip fixed it for me

black -> white?
can you paste the bad image here?

@tg123 exactly. looks like the border color is important. I am using it on a 30300 client build if relevant.

f:SetBackdropColor(0,0,0);

f:SetBackdropColor(1, 1, 1);

@tg123 I'm using android. Tried it with Samsung integrated QR scanner and an app. Only the bottom one works.

Also, if you use https://www.onlinebarcodereader.com/ it only detects the bottom one aswell

I assume it just needs the "quiet zone". My guess is that increasing texture size by 2 blocks in each dimension and offsetting the data part would be the fix for this.

EDIT:https://qrworld.wordpress.com/2011/08/09/the-quiet-zone/

hmmm agree
could you please send a PR or I will fix it this weekend