You can read about them in that thread, which also contains good tips from other members (I like @Griff’s solution a lot, a simple slot on each side where you insert sheets of ply, @stutaylo has an acrylic variant, etc…)
I made them a year ago (for that same reason you mention) as a temporary thing to test, but I now keep them there permanently. Very easy to make: I used thin hard foam (the kind that goes under floors) taped to aluminium corner guards, held to the baseboard using a couple of screws (the small metal brackets you see in the picture are the only thing holding them, it works perfectly)