Monstera Leaf Edges Brown. If your plant is infected isolate it from your other plants and remove the offending leaves with a pair of scissors that you disinfect between each cut. Cut off the affected leaves and read this post on how to give your Monstera great conditions and help it grow.
Move your plant away from the window a bit. Unfiltered water containing adverse chemicals can also cause this issue. This viney plant is easy to maintain but even the hardy Monstera can develop problems such as brown spotting.
Unfortunately there is nothing you can do to fix them or make them green again.
There are a few things to check and see what needs fixing. Leaf spots leaf blights and tip burns can all mean leaves turning brown on philodendrons. Black Spots on Monstera due to Low Humidity. Although Monsteras dont like sitting in water they also dont like their soil being too dry for longer periods of time.