Not a Prusa user, but the title of that bug does look accurate - the first layer is too low. Does Prusa support bed mesh and is there a way of setting the zero point of the bed relative to whatever they’re doing for z-endstop?

In klipper land there are solutions to this, but they’re not baked into the out of the box solution.

On my Voron if I want to guarantee a good first layer, I must:

• let the bed temp stabilize after hitting temp for a bit. The bed is a nice thick piece of aluminum, which helps with consistent temp, but when the thermistor hits temp the top is still a little cool
• wipe the nozzle to get it clean since my printer uses the nozzle for homing z. There are mods to automate this
• bed mesh. This is available out of the box with klipper, but it will be turned off until you configure it and include it in print_start
• I use a z Caliberation macro to align the z height of my z end stop and my klicky bed probe that’s used for bed meshing. When setting this up, you need to make sure to use the same origin point as the bed mesh otherwise your first layer can be too low or too high

My first layer is nearly aways flat. It will occasionally be too high or too low because there was a goober on the end stop or something else along those lines.

Are you sure things are clean? Likewise, are you running a mesh? Have you tried adjusting z-offset up a touch?

Honestly, I would start with first layer squish as you could easily be too low.