While the RP format only aligns with versions between and including 1.21.4-pre1 and 1.21.4 it should still work on most other versions too as it is a very small pack where very specific changes to the pack format is needed for it to break.
46 in 0.1.46 stands for Resource Pack Format 46
This is updated to pack format 46 (1.21.4) to support the latest version of Minecraft.
While the RP format only aligns with versions between and including 24w21a (1.21) and 1.21.1 it should still work on most other versions too.
34 in 0.1.34 stands for Resource Pack Format 34
This is (of course) the first version. For now it's simply just removing the item in the item frame item texture. It just works right now.