Dockmanager in shadow dom & double slotted does not allow input focus

[ig-robstoffers]

When you place an igc-dockmanager inside shadow dom and also double slot the pane content then it is not possible to focus the input. I believe the issue occurs in the handlePaneContentMouseDown where it is checking for the activeElement. In this specific scenario the activeElement is resolving to null when you click on the <input> which causes the pane to manually set focus causing the <input> to lose focus.

version: 1.11.3
browser: Chrome 107.0.5304.88

Steps to reproduce

1. Run attached sample.
2. Try to click inside the <input> element in the content pane.

Result

What is the actual result after following the steps to reproduce?

The <input> is not able to focus.

Expected result

What is the expected result after following the steps to reproduce?

The <input> should be able to gain focus.

Attachments

dockmanager-shadowdom-focus-bug.zip