TextViewer: Flag as a modal (#7255)
TextViewer: Flag as a modal (#7255)

It's used that way in a few contexts (e.g., View HTML).

Fix #7249
NiLuJe/koreader,Frenzie/koreader,poire-z/koreader,Hzj-jie/koreader,NiLuJe/koreader,koreader/koreader,koreader/koreader,Frenzie/koreader,poire-z/koreader,mwoz123/koreader