Chrome Version: 73.0.3679.0 (Official Build) Revision	a6e4408c6b15bb6af7e93df4ad81373f7fadcb94-refs/branch-heads/3679@{#1} (32/64-bit)
OS: Windows(7,8,8.1,10), Mac (10.13.1, 10.13.6, 10.14.3) & Linux (14.04 LTS).

What steps will reproduce the problem?
1. Launch Chrome, open DevTools on NTP and press "Ctrl + P" key to Open file overlay.
2. Select any option from list (For Ex: newtab?ie=UTF-8) and add the breakpoint on any line of code.
3. Right click on added breakpoint to open menu list and select 'Edit breakpoint' option to open edit breakpoint overlay.
4. Now, click to open drop-down list, select 'Breakpoint' option from drop-down list and observe.

Actual: Unnecessary edit breakpoint overlay gets closed on selecting 'Breakpoint' option from drop-down list.
Expected: Edit breakpoint overlay should not close on selecting 'Breakpoint' option from drop-down list.

This is a regression issue, broken in M-73 series, below is manual regression range:

Good build: 73.0.3648.0 (Revision: 618636)
Bad build: 73.0.3649.0 (Revision: 618770)

You are probably looking for a change made after 618765 (known good), but no later than 618766 (first known bad).
CHANGELOG URL:
The script might not always return single CL as suspect as some perf builds might get missing due to failure.
  https://chromium.googlesource.com/chromium/src/+log/031be74fecdf8cab44d8c22555dca4031e920472..046112da39a7a9ec0c14ada2fa541ba731964a18

Suspecting: https://chromium.googlesource.com/chromium/src/+/046112da39a7a9ec0c14ada2fa541ba731964a18

@luoe: Could you please check whether this is caused with respect to your change, if not please help us in assigning it to the right owner.

Kindly review the attached screen-cast for reference.

Thank you..!
 

Deleted: Actual behavior.mp4 1.2 MB

	Actual behavior.mp4 1.2 MB View Download

Deleted: Expected behavior.mp4 647 KB

	Expected behavior.mp4 647 KB View Download