@TomSlavkovsky This bug has disappeared couple of days ago. Now I can see favourites again in the list and I can edit their texts. The weird icons has disappeared already a long time ago. You can close this defect report as SOLVED - thank you!

@TomSlavkovsky OK, I did as you described above and deleted the local storage for Windy application in the Firefox. As a result I lost all my stored favourites from the last 10 days!!! That is altogether 10 x 6 = 60 of them :( So there is also a bug in the code where it writes favorites to a cloud. Deleting the storage didn't fix the the original problem as you see from the picture here:

I have been using Windy now for several months while tracking one of the GGR entrant sailing around the world. I have hundreds of favourites stored in the Windy. Since last Friday I have not been able to edit their texts and delete them. The default text of a created favourite is no longer the coordinates of favourite but some weird icons. Please have a look on attached picture. The OS is 64-bit W7 and the browser is Firefox (latest version).