I find that it’s best to use 65C for the bed temperature for the first couple of layers, and then drop the temperature to 50C. If you’re using Cura, there should be an option to do that, but you’ll need to dig through the advanced settings to find it. Doing this has completely solved warping for me (Ender 3 Pro v1 with PLA filament). My understanding is that it works because the temperature differential between the top and bottom layers causes a pulling force that causes the warping that you see. I think it’s something about the expansion of the plastic due to heat - as the plastic cools down, it shrinks, which pulls the layer below it upward. The wider the base, the stronger the pulling force. And the more layers you add, the more the pulling force compounds, until eventually the print warps.

The solution is simple - minimize the temperature differential. You really only need it to be hot on the initial layer, for the print to stick properly. And afterward you only need to maintain a temp that’s just hot enough that the print doesn’t pop off. Hence, 65C initial, 50C for everything else afterward

Probably less relevant, but I also find that adhesion improves if you have the printer go at half speed for the first couple of layers. Again, there should be a setting in Cura, but it’s in the advanced settings

I find that I can just use these 2 modifications and everything just works. No need for glue. I just dust off the bed when it gets dusty but beyond that, I don’t mess with it. Actually, the adhesion is quite strong. Even after the bed has cooled to room temperature, I have to exert a bit of force to pull the print off the bed