I just ran a test.

I opened up the wall section.
I saved it non compressed.
I saved it compressed.
In the same folder.

I ran the script.
The script de/un-compressed the compressed file.
The script left the non compressed file alone.

The un/de-compressed file was exactly the same file size as the non compressed file after running the script.  So I will assume that the script is clean, and does not really introduce any extraneous code.

Neither PZ3,  loaded into Vue.
Not the non compressed one.
Not the decompressed one.