Chrome Version: 59.0.3030.0 (Developer Debug Build) (64-bit)
OS: Linux

What steps will reproduce the problem?
(1) Install the TraceOnTap extension.
(2) Load a bunch of tabs.
(3) Hit the TraceOnTap icon to take a trace.

What is the expected result?

Expect that the trace eventually completes, and to be prompted for the file to save it to.

What happens instead?

Tracing reaches the "Finalizing" state, and then "Done", but never prompts to allow the user to actually save the trace.  Console log shows:

[27823:27823:0303/143657.768195:INFO:CONSOLE(160)] "TracingController state: attaching", source: chrome-extension://amlnjoelabmgbmhkgejofjdchfcfogdg/tracing_controller.js (160)
[27823:27823:0303/143658.440429:INFO:CONSOLE(160)] "TracingController state: tracing", source: chrome-extension://amlnjoelabmgbmhkgejofjdchfcfogdg/tracing_controller.js (160)
[1:3:0303/143658.586577:ERROR:memory_dump_manager.cc(609)] Disabling MemoryDumpProvider "V8Isolate". Failed to post task on the task runner provided.
[27823:27823:0303/143701.432277:INFO:CONSOLE(160)] "TracingController state: stopping", source: chrome-extension://amlnjoelabmgbmhkgejofjdchfcfogdg/tracing_controller.js (160)
[1:3:0303/143720.822843:WARNING:trace_log.cc(1017)] The following threads haven't finished flush in time. If this happens stably for some thread, please call TraceLog::GetInstance()->SetCurrentThreadBlocksMessageLoop() from the thread to avoid its trace events from being lost.
[1:3:0303/143720.823485:WARNING:trace_log.cc(1025)] Thread: Chrome_ChildIOThread
[27823:27823:0303/143721.347887:INFO:CONSOLE(160)] "TracingController state: idle", source: chrome-extension://amlnjoelabmgbmhkgejofjdchfcfogdg/tracing_controller.js (160)
[1:3:0303/143722.605859:WARNING:trace_log.cc(1017)] The following threads haven't finished flush in time. If this happens stably for some thread, please call TraceLog::GetInstance()->SetCurrentThreadBlocksMessageLoop() from the thread to avoid its trace events from being lost.
[1:3:0303/143722.606381:WARNING:trace_log.cc(1025)] Thread: CrRendererMain
[27823:27823:0303/143728.899741:INFO:CONSOLE(5794)] " [1055.179s] [bcx.Client] [onNetworkError_] net::ERR_ABORTED", source: chrome-extension://aihpiglmnhnhijdnjghpfnlledckkhja/background_compiled.js (5794)

You can run another trace by hitting the icon again, but it still won't prompt to save the results.