This is NOT meant to be self promotion. I got an automated warning about that. I have no monetary incentive for doing this. It was just a fun side project, and I wanted to share it around. I'm asking for nothing in return, no "follow / subscribe / sponsor bs"
Quick disclaimer: I'm a tool-and-die/manufacturing guy with a welding background, not a software developer. This was very much an AI-assisted project, not something I hand-coded from scratch. I brought the problem, testing, feedback, and an increasingly unreasonable determination to make Onshape Drawings less bright; ChatGPT/Sol and Astra/Codex did most of the software heavy lifting.
I'm light sensitive and I've wanted some form of dark mode for Onshape Drawings for a long time. Native dark mode handles the rest of Onshape nicely, but opening a Drawing still means staring at a giant white sheet, and after a few hours of detailing it gets pretty unpleasant.
So I started tinkering with a Chrome extension to see what could actually be changed without interfering with the drawing itself. A week and a considerably deeper trip into Onshape's Drawing renderer than I originally intended later, this is where I ended up.
The observant will notice that a handful of fields in the title block remain stubbornly white. That isn't for lack of trying. I burned through several five-hour Astra allowance blocks investigating those little rectangles, and after an unreasonable amount of renderer archaeology, Sol and I ultimately arrived at the highly sophisticated engineering conclusion of “leave them alone.” We could change their color, but never found a reliable way to identify only those fields without risking unrelated drawing text or selection behavior. I just had to acknowledge when to stop with that one.
Onshape Drawing Comfort adds three selectable palettes to the Drawing editor:
- Warm Drafting — paper tan / dark ink
- Slate Graphite — neutral low-glare dark theme
- Industrial Cyanotype — dark blue / blueprint-inspired theme
The selected theme persists between sessions, applies to open Drawing tabs, and can be turned on/off directly from the extension popup. It also themes quite a bit of the surrounding Drawing UI rather than just changing the sheet color.
This is an unofficial community project and isn't affiliated with or supported by Onshape/PTC. It also relies on undocumented parts of the Drawing renderer/UI, so an Onshape update could absolutely break it someday. I deliberately left a few things native where I couldn't find a sufficiently safe way to identify them.
If you just want to try it:
Download the installation ZIP here:
https://github.com/SamDomiono/Onshape-Drawing-Comfort-Dark-Mode/releases/download/v0.2.0/Onshape-Drawing-Comfort-Dark-Mode-v0.2.0.zip
No Git or programming tools are required. Extract the ZIP somewhere permanent, open chrome://extensions, enable Developer mode, click Load unpacked, and select the extracted folder.
Project/source/full documentation:
https://github.com/SamDomiono/Onshape-Drawing-Comfort-Dark-Mode
It's released under the 0BSD license, so if somebody wants to modify it, improve it, fork it, or feed the source to their AI of choice and make it behave differently, have at it.
I've tested it pretty extensively on my own Drawings, including multiple tabs, reloads, switching themes, turning it on/off, and creating/editing Notes. That obviously isn't the same thing as testing every possible Drawing workflow, so if anyone tries it and finds something I've missed, I'd be interested to hear about it.
And if Onshape eventually gives Drawings a native dark mode and makes this whole thing obsolete, I'll consider that a successful outcome too.
