recommend testing if "font support" (not just the font files) is installed into the docker image. typically docker image operating systems lack many services and facilities that are common for a full desktop or server installation. i'm guessing there is no font support installed into the image because, typically, such support leans on X11 or wayland (or some headless ui proxy framework) support to also be available (as dependencies). this does not look like a POI issue.
Stanton Fisque principal technologist latticeware.com portland, oregon
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