ID 418299 - Panels do not reappear after disappearing when using the MATE desktop environment on Linux.

Problem summary
Panels do not reappear after disappearing when using the MATE desktop on Linux.

Customer reported version
mari.n/a

Customer reported platform
n_a_linux

Steps to reproduce

1) In Mari, close all palettes.

2) Open one palette, such as Color.

3) Wait for it to completely auto-fade.

4) Click the panel to open it again and observe.

Expected behavior
The panel should appear 100% visible when opened a second time after letting it disappear.

Actual behavior
The panel remains invisible or at 0% opacity until hovered over again.

Workaround
There is no available workaround at this time.

Reproduced by Support in
Mari 4.6v1 - CentOS 7 (MATE)

Mari 4.5v2 - CentOS 7 (MATE)

Mari 4.5v1 - CentOS 7 (MATE)

Mari 4.2v2 - CentOS 7 (MATE)

Mari 4.0v1 - CentOS 7 (MATE) - regression

Unable to reproduce bug in:

Mari 4.6v1 - Windows 10, macOS 10.14

Mari 3.4v4 - CentOS 7 (MATE)

Earliest version tested
Mari 3.4v4 - This feature did not exist before this version