Cracked screen flickers -temp fixes?

I broke my screen and there's a bit of glass missing on the edge. A horizontal line has appeared by the crack and the part of the screen below this often flickers green /goes dark. I found that if I play with it a bit it stops, especially I noticed if I push something fine in the crack it comes back to normal for a while (I have resorted to using the back of my earrings for this!).

I am not in a place to buy a new phone yet, and fixing this would cost about the same. My phone works perfectly besides this issue so I would like to use it as long as possible.

I've seen people suggesting to put glue or nail polish on cracked screen, but my hole is so deep I am worried this would ruin the whole screen.

Does anyone have suggestions on what I could safely put there that won't cause further damage?

Thanks !!