ISOLDE 1.2.0 is available, and ready to install for @UCSFChimeraX 1.2! As usual, just get the ChimeraX 1.2 release from https://www.rbvi.ucsf.edu/chimerax/download.html then install ISOLDE via "Tools/More Tools. Code is on GitHub https://github.com/tristanic/isolde.

ISOLDE is a plugin to UCSF ChimeraX, designed to ease the task of macromolecular model building into low-to-medium resolution maps derived from crystallographic or electron cryo-microscopy (cryoEM) experiments.

UCSF ChimeraX (or simply ChimeraX) is the next-generation molecular visualization program from the Resource for Biocomputing, Visualization, and Informatics (RBVI), following UCSF Chimera. ChimeraX can be downloaded free of charge for academic, government, nonprofit, and personal use.

You can view snapshot here https://twitter.com/CrollTristan/status/1390709520876331009