Wingpanel background-based translucency and text color fails on external primary monitor

[fnune]

What Happened

The wingpanel was no longer transparent when I switched on my second monitor and changed backgrounds.

It looks like this:

And sometimes like this:

Expected Behavior

Expected the wingpanel to look like this:

Steps to Reproduce

0. Switch off any external monitors
1. Set the background to something light that triggers the translucent + dark text mode on the wingpanel
2. Switch on an external monitor and set it as primary
3. See how the wingpanel no longer changes its background and text as expected

Platform Information

elementary 5.1.7

[fnune]

I'm wondering if it's these lines running:

https://github.com/elementary/wingpanel/blob/master/wingpanel-interface/Utils.vala#L58-L60

[pongloongyeat]

Just to add that this only applies if your primary monitor is on the left. This issue doesn't seem to occur if you set your primary monitor on the right.

[fnune]

Just to add that this only applies if your primary monitor is on the left. This issue doesn't seem to occur if you set your primary monitor on the right (and change backgrounds to update the panel colour).

I don't have access to the setup with which I took the screenshots above, but I can confirm that my primary monitor was on the right, and it was my external monitor.

[pongloongyeat]

Weird, I thought I got confused but I just retested and that's the only way I can actually get the panel to show the correct colour

[aral]

In case it helps, I’m running into this now and if I run wingpanel manually, this is the error output.

First run (after killing the original process and launching io.elementary.wingpanel):

(io.elementary.wingpanel:2957): GLib-GObject-WARNING **: 16:52:10.136: invalid (NULL) pointer instance

(io.elementary.wingpanel:2957): GLib-GObject-CRITICAL **: 16:52:10.136: g_signal_connect_object: assertion 'G_TYPE_CHECK_INSTANCE (instance)' failed

(io.elementary.wingpanel:2957): libnm-CRITICAL **: 16:52:10.136: ((libnm-core/nm-connection.c:193)): assertion '<dropped>' failed

(io.elementary.wingpanel:2957): io.elementary.wingpanel.notifications-CRITICAL **: 16:52:10.261: NotificationEntry.vala:79: Unable to mask image: Failed to open file “/tmp/wingpanel-6W0N80.png”: No such file or directory

Second run (after killing that process and relaunching again):

(io.elementary.wingpanel:2957): GLib-GObject-WARNING **: 16:52:10.136: invalid (NULL) pointer instance

(io.elementary.wingpanel:2957): GLib-GObject-CRITICAL **: 16:52:10.136: g_signal_connect_object: assertion 'G_TYPE_CHECK_INSTANCE (instance)' failed

(io.elementary.wingpanel:2957): libnm-CRITICAL **: 16:52:10.136: ((libnm-core/nm-connection.c:193)): assertion '<dropped>' failed