With older version of PerfView you can do this:
- Select First/Last columns and press CTRL+C
- Paste in Start and press ENTER
This would update Start/End with both values.
In newer versions this now breaks because copying the times inserts pipes around the values:
Old version:
1,395.251 2,626.358
New version:
| 1,395.251 2,626.358 |
I get bitten by this new behavior daily.