SVG Export suddenly does not export fonts well

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Describe the bug

Exporting diagrams from drawio online app as SVG does not maintain Helvetica font, regardless if I embed or not embed the fonts. This function worked for the exact same file for over a year and suddenly broke.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'File'
2. Click on 'Export as'
3. Scroll down to ' SVG

Expected behavior
The SVG file should use render using the same Helvetica font I specified in the drawio editor.

Screenshots

Both files show the diagram exported svg files with and w/o embedded fonts:

This is how the diagram looks in the drawio online editor (font Helvetica):

This is how the previous export of the diagram looks with correct fonts (last exported a few months ago). This is an operation i've performed on this file and others like it dozens of times successfully:

**draw.io version (In the Help->About menu of the draw.io editor): 27.1.4

**Desktop (please complete the following information):

• OS: MacOS Monterey
• Browser: chrome
• Version: 139.0.7258.155
  I tested the problem in incognito/private mode with all browser extensions switched off, write "yes" below:
• yes

Reproduce the problem in the draw.io online app through File > Export as > SVG, using the reported Helvetica diagram and comparing embedded and non-embedded exports. Trace the SVG export path and font handling, then verify that the exported SVG preserves the selected Helvetica rendering in both cases.