What is the bug or the crash?

We are having troubles with a temporal WMS layer, which has both a group layer and a temporal sublayer.

From the user perspective, using the Temporal Controller, we always observe the same image in the canvas, even changing the time units, range and timestamp.

WMS URL: https://wms.geo.admin.ch/?VERSION=1.3.0
WMS capabilities URL: https://wms.geo.admin.ch/?VERSION=1.3.0&SERVICE=WMS&REQUEST=GetCapabilities

From a more detailed analysis, this is the observed behavior:

• Loading the WMS from QGIS Browser (from stored WMS connections):

  • Group layer is NOT temporal-enabled.
  • Temporal sublayer IS temporal-enabled:
    • QGIS DOES send the TIME parameter, but in a wrong format (e.g., 1953-01-01T00%3A00%3A00Z, instead of just 1953).

• Loading the WMS from Data Source Manager:

  • Group layer IS temporal-enabled.
    • QGIS does NOT send the TIME parameter!
  • Temporal sublayer IS temporal-enabled:
    • QGIS does NOT send the TIME parameter!

Steps to reproduce the issue

1. Go to QGIS Data Source Manager
2. Choose WMS/WMTS and add the aforementioned URL as a new service connection.
3. Connect to the server.
4. Filter results by entering "zeitreise"
5. Load the group layer (i.e., ID 337)
6. Without adding more configuration, open the temporal controller.
7. If needed, choose Years as time units.
8. The displayed image never changes, even moving the slider.

Repeat steps for sublayer with ID 340.

Now, go to the QGIS Browser, access the added WMS connection, drag and drop the group layer. See that it's not even temporal-enabled.

Now drag and drop the sublayer from the QGIS Browser, see that the image never changes, even moving the slider in the Temporal Controller.

Versions

QGIS 3.44.x
QGIS master 3.99.

Supported QGIS version

• I'm running a supported QGIS version according to the roadmap.

New profile

• I tried with a new QGIS profile

Additional context

No response