I'm using lit-element (v2.3.1) & lit-html (v1.2.1) and having a memory leak where as a result of rendering, detached DOM nodes are not cleaned by GC and the only retainers shown for them by Chrome DevTools are WeakMaps used internally by lit-html to keep track of parts:
This doesn't happen with all renders, but I have not found a difference between the templates/renders that do and do not leak. Seems almost random. But maybe I'm missing something obvious here, would be glad to hear any suggestions regarding this.