Embedded fonts are not rendered during a slideshow online

[estux]

Describe the Bug

I have a file with embedded fonts created with Libreoffice on the desktop.
I uploaded the file on a Nextcloud folder and opened it with Collabora (not the "embedded" one but installed on a dedicated server).
The Collabora server (called from Nextcloud) doesn't have the right fonts but I can see the text properly from the editing interface.
When I launch the slideshow the text is messed up as it seems it doesn't read the embedded fonts but fallbacks to some standard font.

Steps to Reproduce

1. Create a file (.odp) with embedded fonts (not included in your Collabora server setup) from Libreoffice desktop
2. Upload the file to Nextcloud
3. Open it with Collabora from the browser (granted that you have a dedicated Collabora server already configured and working together with your Nexctloud)
4. you can see the embedded fonts are working in the editing interface
5. Lanch the (online) slideshow and see that the same fonts are not working anymore; the texts are messed up.

Expected Behavior

I expect the embedded fonts to be visible and working also in the slideshow mode.

Actual Behavior

The embedded fonts are not called during the slideshow mode, generating confusion about the final (rendered) result.

Screenshots

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Desktop

(Please complete the following information)

• Collabora version: 24.04.3.1
• OS and version: Windows 10
• Browser and version: Firefox 132.0.1

Smartphone

(Please complete the following information)

• Device: [e.g. iPhone 14]
• OS: [e.g. iOS 16.5]
• Browser and version: [e.g. Safari 16.4]

Additional Context

Add any other context about the problem here.