Blender
Blender's theme system isn't a CSS file, it's roughly 570 individual color properties on
bpy.context.preferences.themes[0], saved into a binary userpref.blend, not a plain-text
config. So this template doesn't just render a file, input_path is a Python script (with
{{colors.role.default.hex}} placeholders substituted the normal way), and post_hook runs it
through Blender itself in headless mode, which applies the colors via the real bpy API and
saves preferences directly. No GUI window opens, --background mode is fully invisible.
What gets themed, and what deliberately doesn't
Only structural chrome: panel backgrounds, headers, tab strips, widget fills/outlines/text, editor borders, list backgrounds, metadata overlay boxes. Around 345 of the ~570 properties.
The rest (about 225) are left at Blender's own defaults on purpose: mesh-editing selection states (vertex/edge/face colors), node category colors, sequencer strip-type colors, syntax highlighting, keyframe types, axis/gizmo colors. These are workflow conventions users rely on for actual 3D work, not decoration, recoloring them to an arbitrary palette would hurt usability rather than improve consistency. Same reasoning already applied to terminal ANSI colors and Blender's own axis-color convention (X=red, Y=green, Z=blue) elsewhere.
Native install
Runs blender --background --python ... directly. No setup beyond having blender on PATH.
Flatpak install (org.blender.Blender)
Blender's Flatpak has filesystems=host (full host filesystem access), broader than most
sandboxed apps here. $XDG_CONFIG_HOME inside the sandbox is still remapped to
~/.var/app/org.blender.Blender/config regardless, same as every other Flatpak app, but that
doesn't matter for this template: the rendered script lives at a plain host path
(~/.cache/noctalia/blender_theme_rendered.py), and Blender's host grant means it can read
that path directly by its real location, no flatpak override or .var/app-local copy needed
at all.
Testing
Tested against Blender 5.2.0 LTS (Flatpak). Verified via a full audit: captured Blender's true
factory-default theme values (--factory-startup) and diffed against the post-apply state
property by property, confirming exactly which of the ~570 were intentionally changed versus
intentionally left alone, not just spot-checked visually.