no more keepAlive sent after long polling error
The long polling requests for server push were sometimes failing with a
504 timeout. When the website is idle, Wt remembers this as a
commError (in Wt.js) and no longer sends
keepAlive events. Once someone interacts with the page the
keepAlive events will resume since there was a successful request and
commError is cleared.
The reason this was a problem is because for the website in question multi-session cookies were enabled. These cookies are quite short-lived and only get refreshed by the