UI: Make button radius match default window radius (#7054)
UI: Make button radius match default window radius (#7054)


koreader/koreader,Markismus/koreader,NiLuJe/koreader,Hzj-jie/koreader,Frenzie/koreader,koreader/koreader,Frenzie/koreader,poire-z/koreader,poire-z/koreader,pazos/koreader,mwoz123/koreader,NiLuJe/koreader