I have some tags like this: !not finished, +favourite, -deleted,... After typing "!", "+" or "-" as first character, the tag completion didn't appear (Tags start with alphabetical character work just fine). I created
ticket #9028 and kovidgoyal said it worked for him. I think there is something wrong in my configuration but I don't know what is. Could anyone check this and/or have the same problem? Thank you very much.