onboard crashes on launch

If you don't mind running non-release versions of Onboard, you might try the updated version available in our PPA:
https://launchpad.net/~onboard/+archive/ppa

By the way, the version in the PPA also includes two new layouts, that resemble more the layouts found on mobile devices.

Status changed to 'Confirmed' because the bug affects multiple users.

I tried revision 1627 from the PPA (0.99.0+1627-0ppa~saucy1). I am running Kubuntu Saucy in VirtualBox. And it is crashing for me, too. The output from the terminal is:

htpc@htpc-VirtualBox:~$ onboard
Traceback (most recent call last):
  File "/usr/bin/onboard", line 16, in <module>
    ob = Onboard()
  File "/usr/lib/python3/dist-packages/Onboard/OnboardGtk.py", line 111, in __init__
    self.init()
  File "/usr/lib/python3/dist-packages/Onboard/OnboardGtk.py", line 210, in init
    self.keyboard_widget.set_startup_visibility()
  File "/usr/lib/python3/dist-packages/Onboard/KeyboardWidget.py", line 327, in set_startup_visibility
    self.commit_transition()
  File "/usr/lib/python3/dist-packages/Onboard/KeyboardWidget.py", line 546, in commit_transition
    self._on_transition_step()
  File "/usr/lib/python3/dist-packages/Onboard/KeyboardWidget.py", line 583, in _on_transition_step
    window.set_visible(visible)
  File "/usr/lib/python3/dist-packages/Onboard/KbdWindow.py", line 288, in set_visible
    self._show_first_time()
  File "/usr/lib/python3/dist-packages/Onboard/KbdWindow.py", line 169, in _show_first_time
    self.pre_render_keys(*self.get_size())
  File "/usr/lib/python3/dist-packages/Onboard/KbdWindow.py", line 178, in pre_render_keys
    self.keyboard_widget.pre_render_keys(self, w, h)
  File "/usr/lib/python3/dist-packages/Onboard/KeyboardWidget.py", line 345, in pre_render_keys
    self.render(context)
  File "/usr/lib/python3/dist-packages/Onboard/LayoutView.py", line 204, in render
    item.draw_cached(context)
  File "/usr/lib/python3/dist-packages/Onboard/KeyGtk.py", line 128, in draw_cached
    surface = self._create_key_surface(context)
  File "/usr/lib/python3/dist-packages/Onboard/KeyGtk.py", line 147, in _create_key_surface
    self.draw(context)
  File "/usr/lib/python3/dist-packages/Onboard/KeyGtk.py", line 155, in draw
    self.draw_image(context, lod)
  File "/usr/lib/python3/dist-packages/Onboard/KeyGtk.py", line 483, in draw_image
    pixbuf = self.get_image(rect.w, rect.h)
  File "/usr/lib/python3/dist-packages/Onboard/KeyGtk.py", line 709, in get_image
    new_from_file_at_size(filename, width, height)
gi._glib.GError: Unrecognized image file format

I don't know where I can find the log files - so I've written print(filename) in an appropiate place. The image file mentioned is /usr/share/onboard/layouts/images/erase.svg, I hope that helps.

Thanks for trying the PPA, Jörn.
You can get a debug log that shows the file names of loaded images with
$ onboard -ddebug
 but now that you found the file, I think I won't need this anymore.

Does this print anything?
$ /usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/gdk-pixbuf-query-loaders | grep -i svg

Does this make a difference?
$ sudo apt-get install librsvg2-common

Please attach that svg file /usr/share/onboard/layouts/images/erase.svg here.

It works now, with librsvg2-common - but I am not 100% sure, if that fixed it. If you want I can set up a VM tomorrow and check that. Just for the records, the erase.svg:

joern@joern-notebook:~$ cat /usr/share/onboard/layouts/images/erase.svg
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!-- Created with Inkscape (http://www.inkscape.org/) -->
<svg id="svg2985" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns="http://www.w3.org/2000/svg" height="16" width="16" version="1.1" xmlns:cc="http://creativecommons.org/ns#" xmlns:dc="http://purl.org/dc/elements/1.1/">
 <metadata id="metadata2990">
  <rdf:RDF>
   <cc:Work rdf:about="">
    <dc:format>image/svg+xml</dc:format>
    <dc:type rdf:resource="http://purl.org/dc/dcmitype/StillImage"/>
    <dc:title/>
   </cc:Work>
  </rdf:RDF>
 </metadata>
 <rect id="rect3760" style="color:#000000;stroke:#000;stroke-width:.75;fill:none" ry="0" height="7.2" width="9.6" y="4.7" x="3.2"/>
 <path id="path3764" style="stroke:#000;stroke-linecap:round;stroke-width:.75;fill:none" d="m6.3456 9.9543 3.3088-3.3087"/>
 <path id="path3772" style="stroke:#000;stroke-linecap:round;stroke-width:.75;fill:none" d="m9.6544 9.9543-3.3088-3.3087"/>
</svg>

Yes, the missing librsvg2-common must have been the reason. That package wasn't on our radar before, but I see now we have only a suggest dependency via libgtk-3-0. I could imagine a fresh Kubuntu not having it. If you'd like to confirm this, yes please, try a new VM.
In any case, we better add that package as a direct dependency of Onboard.

I have double-checked that, librsvg2-common was the missing dependency.

Thank you, I've added the dependency and improved the error handling in trunk.

This bug was fixed in the package onboard - 1.0.0-0ubuntu1

---------------
onboard (1.0.0-0ubuntu1) trusty; urgency=low

  * Request for sponsorship for new upstream release (LP: #1282231)
  * debian/control:
    - Raise Standards-Version to 3.9.5
    - Add librsvg2-common to Depends for Kubuntu (LP: #1204896)
  * debian/onboard.install:
    - Use usr/share/onboard/onboard-defaults.conf* instead of single entries
    - Add the usr/share/onboard/tools/checkmodels file
  * debian/patches/add_defaults_for_ubuntu.patch:
    - Update add_defaults_for_ubuntu.patch with values for this release
  * Word suggestions enhancements:
    - Every language id now has its own user language model
    - Add a checkbox to the Preferences to show the language switch on layouts
    - Add a checkbox to the Preferences to show the pause learning button
    - Add Canadian English system language model
    - Add Danish system language model
    - Add various flavors of the Dutch system language model
    - Add Gaelic system language model
    - Add Greek system language model
    - Add Irish system language model
    - Add Luxembourgian system language model.
    - Add Polish system language model
    - Add Romanian system language model
    - Add Swedish system language model
    - Add Turkish system language model
    - Update Brazilian system language model
    - Improve makemodels script
    - Add model_info tool
    - Add checkmodels tool to diagnose language model loading errors
    - Add tool to randomize sentences in corpora
    - Add copy function to allow transfer between language models
    - Add smart support for camel-case words (Thanks Michael Bauer)
    - Make language switcher more user-friendly (Thanks Michael Bauer)
    - Stop word correction when spell checker dictionary is not present
    - Fix learning of text spans larger than 100 characters
    - Fix word suggestions sometimes being unaware of modifier presses
    - Fix all upper-case words not being suggested at sentence begin
    - Fix wrong caret position in rename function of Nautilus
    - Fix some character deletion on focus change after a word completion
    - Fix bit rot in split_corpus tool
    - Improve handling of the / and other non-word tokens
    - Improve support for URLs and directories
    - Don't learn passwords from URLs
    - Show dialog on language model loading error (LP: #1278599)
  * Layouts:
    - Add support for polygonal keys instead of only rectangles (LP: #1259371)
    - Make the Return key of the Compact and Full Keyboard layouts a polygon
    - Don't write suggestions outside prediction area in Onboard
    - Grid layout: add settings,move,hide,quit and click buttons (LP: #754391)
    - Add Whiteboard and Whiteboard wide layouts (contributed by Johannes Almer)
    - Add short and long description to the layouts
    - Perform small visual improvements
  * Change the design of the layout section in the Preferences
  * Tweak themes lightly
  * Click buttons:
    - Add support for new mousetweaks branch (version >= 3.9)
    - Fix CSClickMapper sometimes erroneously claiming to be active
  * Add dependencies check to setup.py
  * Add gsettings key to choose between App...

This bug should be fixed with the 1.0.0 release. If you still encounter problems, please feel free to reopen this bug or file a new one.