This issue contains references to a number of ToolTip issues. It is intended as a convenience for search, and a collection point for common information. Please limit discussion to topics common to the collection as a whole; comments about the individual bugs should go into the appropriate linked issue.

The issues collected here are

• Issues present in .NET 4.8 and above (i.e. .NET Core 3.x, .NET 5.x, previews of .NET 6.0)
• Actual bugs, as opposed to design changes
• Contrary to, or blocking of, the new ToolTip behavior mandated by the WCAG 2.1 compliance work. See the spec
• Fixed by that work (in .NET 6.0)
• Not planned to be fixed in any earlier versions

Here is a sample app that illustrates most of the issues (see individual bugs for repro steps):
WpfApp3.zip
The app artificially sets all tooltips to delay for 5 seconds before opening, and to close after displaying for 15 seconds. This makes it easier to see the behavior, but does require a little patience.