Thunderbird has worked fine on my new laptop for several months. Today, I was using it as usual, when all emails w/in folders disappeared. The space is blank with each folder, which are all still displayed like normal, but now diagonal pink lines exist - nothing shows in any columns Subject, Correspondents, Date, etc. (see screenshot). I'm still receiving emails like normal because I see them displaying in the lower right corner of the screen when they arrive, but the do not show up in Inbox folder. Must be a Thunderbird problem (I may have accidentally hit a key to cause this?) because I'm still able to see all emails on my smartphone. Any ideas are appreciated; thanks.