Opening files is slow on some internet connections

[wifi-left]

In China, opening .dat files with the newest plugin is very slow
But in the version 0.6.8, it was very fast
I found that if I didn't have access to raw.githubusercontent.com, the file would be hard to open, or impossible to open

[reserveword]

suggestions for implementation: disable rendering feature when texture loading failed, or simply use default(transparent or purple-black) texture as default.

[wifi-left]

Could you please consider adding an option to read NBT files in a standalone mode, which would prevent it from loading resources via the network?
This modification might address the issue of excessively slow file opening caused by network instability.