[ Good News! ] With Solid Explorer v3.2.4 (Beta), the app now launches and works normally even if the optional icon set “Paper Icon for Solid Explorer” is installed. Yay! [ NEW!!! ] The additional icon set no longer works with Solid Explorer v3.x. Solid Explorer crashes whenever this icon set is installed. I strongly hope that either this icon set or the Solid Explorer app itself will be updated so that they work together properly again.