Polymer.Base.async changes the text content of a node with an attached MutationObserver to get its callback called with microtask timing. Polymer.dom(...).observeNodes also uses a separate MutationObserver when available. Polymer.Base.async, because it only has one mutation observer, flushes all callbacks synchronously when its MutationObserver is called. So, all callbacks given to async occur before any other MutationObservers triggered after the first async call.
notwaldorf
commented
8 years ago
Polymer.Base.asyncchanges the text content of a node with an attached MutationObserver to get its callback called with microtask timing.Polymer.dom(...).observeNodesalso uses a separate MutationObserver when available.Polymer.Base.async, because it only has one mutation observer, flushes all callbacks synchronously when its MutationObserver is called. So, all callbacks given toasyncoccur before any other MutationObservers triggered after the firstasynccall.