Re: MPLAB X v5.20 or v5.25 never finishes the installation?
I had what appears to be the same problem: mplabx version 5.30 goes through the entire install (non-graphic mode, as for the last several versions won't run graphic install in a root environment via "su", and I won't log in as root any other way.) Then it hangs. If you kill the install, the result won't run (gets streams of java errors.) Tried twice, same result.
This was on one machine running Debian linux 10, not windows, though.
Oddly, another machine running Debian linux 10 allowed the install without a problem. So I simply used tar to bundle the mplabx v5.30 directory on that machine and restored on the other machine, fixed up the other pieces manually, and the result runs fine, so far as I can tell.
I don't recommend this, for obvious reasons, but I merely report it for those who may be interested.