Any button that's supposed to launch an external program or open a folder does nothing. This includes "Open Resource Pack Folder," "Open in browser" (under both the "Give Feedback" and "Report Bugs" menus), and both "Realms News" and "Extend subscription."

Because of this (or perhaps in addition to this; I'm making a separate issue for it) I haven't been able to identify the appropriate folder for installing resource packs. I have followed the wiki's instructions for directly loading a resource pack, but the folder does not exist. Manually creating it & pasting the resource packs into the folder does not make them show up under available resource packs in-game. Minecraft is installed on a separate drive from the OS, if that's relevant.