Browser action sidebar collapse button doesn't work

[twschiller]

Context

• Use Messenger for sidebar bricks #1642

Stack Trace

browser-polyfill.js:1213 Uncaught (in promise) TypeError: Error in invocation of runtime.sendMessage(optional string extensionId, any message, optional object options, optional function responseCallback): Could not serialize message.
    at browser-polyfill.js:1213
    at new Promise (<anonymous>)
    at wrappedSendMessage (browser-polyfill.js:1207)
    at Object.apply (browser-polyfill.js:891)
    at sendMessage (index.js:111)
    at RetryOperation._fn (index.js:50)
    at RetryOperation.attempt (retry_operation.js:116)
    at index.js:48
    at new Promise (<anonymous>)
    at pRetry (index.js:39)