I’m running 3D printer on my LAN and the slicers use gtkwebkit to connect to the Klipper web interface on the printer. I’m using prusa-slicer and it has an option to generate a CA certificate that is stored on each device that attempts to connect to the 3D printer. I mainly want to be able to monitor the webcam periodically for print failures.
I can connect to the Klipper interface in firefox-esr and my gtkwebkit based browser. Starting prusa-slicer from the command line gives a warning message about a missing token but the fatal error has to do with wxTreeCtrl:
[2025-12-25 10:00:53.027513] [0x00007efcc01e04c0] [error] UserAccount: Failed to read token - no datafile found.
(prusa-slicer:28566): Gtk-CRITICAL **: 10:00:53.216: gtk_distribute_natural_allocation: assertion 'extra_space >= 0' failed
10:00:53 AM: Debug: window wxTreeCtrl@0x560b59434c10 ("treeCtrl") lost focus even though it didn't have it
10:00:53 AM: Debug: window wxTreeCtrl@0x560b59434c10 ("treeCtrl") lost focus even though it didn't have it
10:00:53 AM: Debug: window wxTreeCtrl@0x560b59434c10 ("treeCtrl") lost focus even though it didn't have it
10:00:53 AM: Debug: window wxTreeCtrl@0x560b59434c10 ("treeCtrl") lost focus even though it didn't have it
10:00:53 AM: Debug: window wxTreeCtrl@0x560b59434c10 ("treeCtrl") lost focus even though it didn't have it
One though I had was if I went to the trouble of generating a CA certificate, could it be set up on my OpenWRT router and serve the entire LAN. I did try searching and most forum hits had to do with secure router access. Any pointers on correct search terms or links to setup guides appreciated.
Why do you think the error is related to a missing CA certificate? I’d expect that to show a SSL or HTTPS error or secure connection failed or similar.
Regarding what you are asking, it is not really possible. It would be a major security risk of browsers trusted CA certificates served from a network device (Barring an enterprise management solution or a custom software update server which doesn’t sound like your goal)
The first line of the error message is that UserAccount: Failed to read token - no datafile.
My cursory read of how CA authentication works is that a token is involved. In firefox-esr, it will open via http port 80 but I do not have the ability to specify http vs https in prusa-slicer. So it was a guess.
Yes , although the documentation suggests that setting up login credentials is optional. The other messy part is Klipper is an OpenSource Community effort that includes some nifty features that improve print quality like resonance compensation. The printer I bought uses klipper.
The downside of my purchase is the gcode generator; OrcaSlicer. It is a misama of code. IMHO, the code quality of PrusaSlicer is much better - at least it does not generate lines of error messages when you start it. I think Prusa forked the Klipper web interface (Mainsail) for Prusa-connect.
Prusa Slicer does have webkitgtk4 as a dependency and I suspect a bug when a user account, with token, is not set up. It does have a wizard for configuring the printer wifi connection that generates an encryption key and a token. I dislike blackbox configuration and manually set a static IP on the printer with the wpa2 key. I can ping the printer IP and access with Firefox-esr via http://.
This is drifting off topic. The easiest work around for me is to use Firefox to access the printer and I just asked the question using the router as a CA certificate server as it is capable of being an NTP server along with packages for mail servers, mpd, etc.
I’m printing a part of a prototype and it’s development is a higher priority than sorting out what the problem is connecting through Prusa-Slicer. I’m OK closing the issue since earlier posts say that setting up a CA server on the router is not possible and would be a security risk.