Draw io does not allow usage of loaded custom Tamil font

[user3477071]

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Describe the bug
Unable to use self typing tamil font in draw io

To Reproduce
Steps to reproduce the behavior:

1. Go to
   https://www.azhagi.com/innovative-fonts-unique-and-special.php

   Download the file
   Azhagi.Com-SaiIndira-Bilingual-PhoneticTransliteration.ttf

   Double click on the downloaded ttf file from inside Ubuntu File Manager and click on the
   'Install' button in the top right corner. This will copy the .ttf file to
   $HOME/.local/share/fonts/Azhagi.Com-SaiIndira-Bilingual-PhoneticTransliteration.ttf

   At this point we have successfully installed a self typing tamil font in Ubuntu OS to be available in all
   applications.

   The full name of this font is
   $ otfinfo -i Azhagi.Com-SaiIndira-Bilingual-PhoneticTransliteration.ttf | grep Full
   Full name: Azhagi.Com-SaiIndira-PhoneticTr

2. Startup desktop drawio app which was installed using the commmand
   $ sudo snap install drawio

3. Add a text box to the diagram and in the right tab click on the 'Text' tab and from the 'Font' drop down
   choose 'Custom...' option to bring up the popup which will have 'System Fonts' check box automatically
   selected. In the 'Font Name' section, enter 'Azhagi.Com-SaiIndira-PhoneticTr.

   At this point Font inside 'Text' tab in right panel will be set to
   Azhagi.Com-SaiIndira-PhoneticTr

4. Click inside the added text box in the diagram. At this point, the Font which was just a moment ago
   set to
   Azhagi.Com-SaiIndira-PhoneticTr
   will automatically change to
   Times New Roman
   For some reason the draw io does not recognize the custom font loaded moments ago.
   Any attempt to choose
   Azhagi.Com-SaiIndira-PhoneticTr
   from the Font drop down is immediately rejected and does not stay as a selected font

Expected behavior
The draw io application should allow input of characters using loaded custom font.

• draw.io version 28.2.5

Desktop (please complete the following information):

• OS: Ubuntu

• Browser [e.g. chrome, safari]: Standalone application, browser not applicable

• Browser Version [e.g. 22] Not applicable

[user3477071]

The same font installed in Ubuntu is successfully available for use inside the LibreOffice 'Draw' application.