How Level is Level

It has been said that the LPG fridge from 40 yrs ago were much more critical as far as level, compared to the last 20 yrs. As it is now, its not worth thinking about. If you're living in it, its most likely plenty ok. And if you're not, turn it off if not reasonably level.

I set up a industrial laser level every time we pull over.
Seriously, Half a level in the bubble is more than good.

According to Dometic;

Any time the vehicle is parked for several hours with the
refrigerator operating, the vehicle should be leveled to
prevent this loss of cooling. The vehicle needs to be
leveled only so it is comfortable to live in (no noticeable
sloping of floor or walls).
When the vehicle is moving, the leveling is not critical,
as the rolling and pitching motion of the vehicle will pass
to either side of level - keeping the liquid ammonia from
accumulating in the evaporator tubing.

I have found out that front to back of the ref does not make much difference as when you open vent door and look at "tubes", they run zigzag side to side at a downward angle. I have been off by as much as 3 or 4 inches, side to side of trailer, or front to back of ref for 4 days and it worked fine.
Even had the front of trailer about 3 or 4 inches to high, but as long as I checked "tubes" and all of them had a positive slope down, (none level) ref. worked fine.

I use the ksg5000 method.

Technically, the camper can be surprisingly angled and still have the refrig work. What I have read is that over time, sometimes a long time, a small amount of out-of-level on a regular basis can slowly cause issues with the refrig.

Many, many threads and years ago, someone here suggested leveling your camper until your Stove is level - makes cooking so much easier. If your stove is level but your refrig is out of level, your camper has much more serious issues than leveling!

Should be a number of threads on this subject - try the forum search feature and you should get plenty of opinions.

I forget the specifics but he fridge manufacturers provide the number of degrees that the fridge can be off level - you can convert that into inches based on the size of your rig. When I did the calculation it became obvious that in my rig anything that I would consider comfortable to camp in would be well within the limits of the fridge. After than I stopped being overly concerned about being "level".