Fix Wiki save as epub crash on certain pages (#3231)
Fix Wiki save as epub crash on certain pages (#3231)

* Fix Wiki save as epub crash on certain pages

When first images don't have a height or width attribute
NiLuJe/koreader,mwoz123/koreader,koreader/koreader,Markismus/koreader,poire-z/koreader,Frenzie/koreader,mihailim/koreader,lgeek/koreader,houqp/koreader,apletnev/koreader,koreader/koreader,poire-z/koreader,Hzj-jie/koreader,NiLuJe/koreader,pazos/koreader,Frenzie/koreader