small leaf burn on autoflowering

Good lord almighty... why do you have two plants in the same pot? It's not going to end well, my friend... you can't transplant autoflowers and I can't imagine they're going to do well in such a small pot. I would suggest you choose the weakest plant and simply cut it off at the soil and let the other plant live alone... The mark you seem to be concerned with doesn't have anything to do with light burn - and it's not anything I would worry about at all, either. It was on one of the very first leaves and their usefulness will diminish over time - that stem will certainly never bear a bud site so ignore it. I'm more concerned that you've set yourself up for failure by having two plants in the same pot.... if you've never seen the size of a root ball, I grow DWC and frequently have to change/clean my bucket... and once in a while I take a video of that process. If you look at this, I've got a video - these are the roots that one plant has grown by Week 6 (first week of flowering for this lady).... growdiaries.com/diaries/154058-grow-journal-by-growinggrannie/week/864034 Good luck....

Sometimes plants drop a greener aspect when growing before developing the leaves completly, but in your case i suppose it's calcium and magnesium deficiencie because of the aspect . Make it under control and supplement, remember that's still a baby and dont need much to recover! Good Luck!🌿🌴🌱🌱

I think most likely this is just superficial damage and not to sorry - could've been damaged by the seed casing falling off early on or had water splashed on it and evaporated off. I'd chop or tuck that leaf though to stop it blocking the other plant. Train them to grow in opposite directions, otherwise you'll end up with one big dominant plant and one very small one. Good luck!