Chrome version: 69.0.3497.95 (Chrome OS)
URL: https://chromeperf.appspot.com/group_report?sid=c492cbf340ce5c0f372f9202cf93cf377af803a45d2c2917f7de66c596c4651d

Please copy and paste any errors from JavaScript console (Ctrl+Shift+J to open):
Uncaught TypeError: Cannot read property 'map' of undefined
    at HTMLElement.onTriaged (alerts-table.html:1220)
    at HTMLElement.handler (polymer.html:507)
    at HTMLElement.fire (polymer.html:1294)
    at HTMLElement.<anonymous> (triage-dialog.html:197)
chart-container.html:2132 Uncaught TypeError: Cannot read property '0' of null
    at HTMLElement.onBugTriaged (chart-container.html:2132)
    at HTMLElement.fire (polymer.html:1294)
    at HTMLElement.<anonymous> (triage-dialog.html:197)

Please describe the problem:
ChromiumPerf/mac-10_13_laptop_high_end-perf/rendering.desktop / percentage_smooth / has an alert that is very far from the real problem. The alert was set from a large dip caused by a recent opposite change so I assume that was just caused by some revert. But afterwards there is another dip which seems significant but seems to be too far to be nudged from the original alert.

Is there a way to create a bug from a point in the graph? The "Bisect" option asks for a bug ID but I see no way to create a bug (instead I would need to create the bug manually?).