the fix for this is now listed on the XQuartz GitHub issues page:
it is the same issue that was identified for IDL 8.5.1 and XQuartz 2.7.10:
[CODE]https://www.l3harrisgeospatial.com/Support/Self-Help-Tools/Help-Articles/Help-Articles-Detail/ArtMID/10220/ArticleID/15188/XQuartz-2710-is-Not-Compatible-with-ENVI-531-and-IDL-851