I\'m opening some old VB.NET projects in Visual Studio 2015 and when I edit the code, VS changes the syntax:
It removes \"_\" in concatenations:
\'Be
Just CTRL-Z to undo the removal of the underscores right after Visual Studio (2015-19) "fixes" it for you. This leaves the "Pretty Listing" feature turned on but restores the missing underscores. Thanks David Carta for the answer left as a comment.