I reported this 2 weeks ago. It's always been a bit of a struggle plant. It was fine on Sunday this morning I go to check the soil and saw those strange marks on the leaves. Never seen this before and none of my other plants near it have this.

When you transplanted your Monstera in a larger container you increased your water volume. The extra water in the container has not had time to evaporate. Browning is an indication of too much water. A plant pushes water through to the edge of its leaves, and if given in excess, this can cause veins at the edges to burst, which leads to browning.

You can try to save it by taking away some of the extra new soil in the container. Gently remove as much as the soil on top as you can without damaging the roots. Let your plant dry out well in a room with bright indirect light with a oscillating fan to help the soil dry. Good luck

I am going to share your photo with some friends and see what they say

The first impression they had was overwatering. I asked them because, I don;t grow Monstera as a houseplant. So overwatering is never an issue for me. I think Luke is 100% correct.

It may also be reacting to damage done to some of the roots during repotting. If you are careful not to over water, future leaf damage should be limited.