matrix-react-sdk

df3fe513 - Fix error about MessagePanel not being available for read markers

Fix error about MessagePanel not being available for read markers Stacktrace: ``` TimelinePanel.js?b9ae:1139 Uncaught (in promise) TypeError: Cannot read property 'getBoundingClientRect' of null at Object._getLastDisplayedEventIndex (TimelinePanel.js?b9ae:1139) at Object.updateReadMarker (TimelinePanel.js?b9ae:751) at Object._callee$ (TimelinePanel.js?b9ae:613) at tryCatch (runtime.js?4422:45) at Generator.invoke [as _invoke] (runtime.js?4422:271) at Generator.prototype.<computed> [as next] (runtime.js?4422:97) at asyncGeneratorStep (asyncToGenerator.js?56ef:3) at _next (asyncToGenerator.js?56ef:25) ```