Clicking on Symbols causes "SPDocument::doUnref(): invalid ref count! -1"

Steps to reproduce:

  • open Inkscape
  • Shift+Ctrl+Y to open "Symbols" docking window
  • select "Flow Chart Shapes" as the symbol set (with other sets it's also reproducible)
  • click over any of the symbols twice or more times

What happened?

Inkscape logs the following message that seems to be an unexpected application state:

SPDocument::doUnref(): invalid ref count! -1

What should have happened?

No error message should arise.

Inkscape Version and Operating System:

  • Inkscape Version: 1.0alpha (9bc632663a, 2019-02-08)
  • Operating System: Linux Debian 10 "buster"
  • Operating System version: Linux Debian 10 "buster" 64-bit // 4.19.0-2-amd64 #1 SMP Debian 4.19.16-1 (2019-01-17) x86_64 GNU/Linux
  • Window Manager: Gnome Version 3.30.2
  • Display Server: Xorg

Thank you for filling in a new bug report!

More details on how to write a good bug report can be found at https://inkscape.org/contribute/report-bugs/. Please remember that Inkscape is developed mostly by volunteers in their spare time, and may not be able to respond to reports quickly.