PubSubHubbub prevent subscribing too often in case of error
PubSubHubbub prevent subscribing too often in case of error

https://github.com/FreshRSS/FreshRSS/issues/939

aledeg/FreshRSS,marienfressinaud/FreshRSS,romibi/FreshRSS,marienfressinaud/FreshRSS,romibi/FreshRSS,FreshRSS/FreshRSS,marienfressinaud/FreshRSS,Alkarex/FreshRSS,romibi/FreshRSS,romibi/FreshRSS,Alkarex/FreshRSS,aledeg/FreshRSS,FreshRSS/FreshRSS,Dolomich/FreshRSS,Alkarex/FreshRSS,aledeg/FreshRSS,Alkarex/FreshRSS,marienfressinaud/FreshRSS,FreshRSS/FreshRSS,FreshRSS/FreshRSS,Dolomich/FreshRSS,Dolomich/FreshRSS,aledeg/FreshRSS