So this release is exciting for me, because it contains my first ever open source contribution, in the form of a setting that allows one to disable that annoying dialog box that pops up when you close a window with multiple open tabs.
> set "confirmCloseAllTabs" to true at the top of your profiles.json file
I find your interpretation slightly preferable over what was actually implemented in this case.
"When set to true closing a window with multiple tabs open WILL require confirmation. When set to false closing a window with multiple tabs open WILL NOT require confirmation."
I just checked it and indeed setting it to "false" turns off confirmation.