1/4" to 3/8" sometimes even 1/2" is all well within tolerances.

You can get a sweep for the bottom of the door if you don't already have one.

Here you are.

Hey Millworkman, which one would be good for the sides of the doors? I looked at your link. My shower people said that If I wanted the sides fitted, they would do it. That was several years ago. I am the only one showering so I am careful not to aim the water against the hinge side of the doors. This summer I will have a house full of guest and a lot of showers :) But, you remember my shower door debacle right? where I ended up with 3 sets of doors, and finely I got the whole thing for free? Well the local guys were great, but I thought maybe I'd just add this water catching strip myself. I kinda want to fade from their memory and not ask the local guys about fitting, at this later date.

Also, can these gaskets be removed for cleaning, like the bottom sweeps?

Sorry for the hijack, but might be relevant to OP.

enduring, if you mean sides of the door, yes. Depends on the gap but either of these in the appropriate size glass thickness would be sufficient.

Or this one

The glass is against my wall, at right angles. The second pic looks like it would work. At each end of these "french doors"

Millworkman, So the length would need to be cut to go on either side of the hinges. Is that right?

Correct, I believe they come in 10' pcs

I just measured the gaps, while most are 1/4" there is a space near the bottom of the door that is more like 1/2". This piece you've shown is for 1/4" gap. Will it work with the 1/2" if I just don't snap it on all the way, and have it only partially encasing the door edge?

If there's a sweep at the bottom, does that mean you can't put a matt there? The sweep at the bottom of my frameless door makes a speaking sound when sliding across the tiles. Is that normal?

You can use a mat as long as the sweep does not get hung up on it, if it does try a thinner mat maybe. If it makes a squeaking sound it may be a hair to low, but you may not be able to make it any higher. It will not be an issue the vinyl blades may wear down a bit from the tiles and rubbing which also will not be an issue overall.