Invalid report cause the reporter uses a resourcepack with all of the old default textures (pre 1.15 iirc) which all cause the mentioned errors. (old enchantment glint texture, old (ender) chest texture etc.)
The problem is that as of 1.14 UVs with a size of 0 on either axis will cause z-fighting
It can be resolved by making the UV even slightly bigger
Make sure your identifier doesn't contain any : in it (so something like this would be wrong: "geometry.example:example_model" while "geometry.example.example_model" would be correct)
If that doesn't fix it you might need to attach the model that causes that error
Edit: Aaand I just noticed this post was made 3 months ago, so that answer probably won't help anymore either.
@Onnowhere one thing that should still be mentioned is, that while all item models of blocks now support transparency again, they no longer support translucency/semi-transparency (which was the case in 1.14)
based on what I read in MC-154642 it seems like the player death sound uses the entity.generic.death sound event in certain situations (seems like it depends on if it is yourself or some other person dying).
Are you using a name that contains a capital letter in the structure block maybe?
If yes, try writing something that contains only lowercase letters and see if you can press "Save" now.
If no, can you provide a screenshot?
Do you by chance mean that you cannot see and/or get the advancements?
The area might be too big for the structure blocks to fully encase.
Iirc it can only go 32 blocks in each direction.
It might have to do with https://bugs.mojang.com/browse/MC-129491 , maybe?
TL; DR
According to the comments there (and my own testing in 1.14.1) it seems like that the "location" trigger only detects "features" (stronghold, end cities, shipwrecks etc.) around y 90 for some reason.
Can confirm that this is still an issue in 1.14.1
(and still seems to work around y:90 (as stated in the previous comments) for some reason)
@Purple Pixel Every item can hold any arbitrary data. So unfortunately just cause it can have the nbt doesn't mean it does anything with it when you place it down.