[fix] Wallabag: fix for un-configured plugin error (#4277)
[fix] Wallabag: fix for un-configured plugin error (#4277)


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