If you are sure that you found a bug or if one of the FLTK developers
requested you report a bug from one of the discussion groups, open a
To report bugs or create a PR, you need to be a registered GitHub user.
When reporting a bug:
First verify that the issue has not already been reported
- GitHub Issues is not for questions about how
to use FLTK. For that, see
'General Questions/Discussions' below.
- If you can find the issue in our old STR system
or Roadmap, please refer to it by the
STR number (e.g. "STR 1205") or link to it directly.
- When reporting bugs, be sure to always include:
- The FLTK version (e.g. 1.3.5)
- The platform/distribution (e.g. Windows 7, macOS 10.12,
Ubuntu Linux 16.04 …)
- The compiler + version (gnu c++, clang, Xcode 12, Visual
Studio 2019, MSYS/MinGW …)
If you can provide a (source code) solution you may also clone our
FLTK repository and create a
GitHub Pull Request (PR).
Please read the documentation about our
to be sure your code can be accepted.
If reporting a bug on the website, be sure to include a link to
Requesting New Features (RFE's)
If you want to discuss issues of the FLTK library itself and its
development or if you have suggestions to improve FLTK, please go to
developer forum first, before filing a GitHub Issue or PR to request
a feature (RFE - Request For Enhancement).
General Questions / Discussions
If you are new to FLTK, or have general questions about how to
use FLTK, or aren't sure if you found a bug, ask first on the
If you're sure you found a bug in FLTK, then file a GitHub Issue
described above under 'Reporting Bugs'.
Old FLTK "Software Trouble Report" (STR's)
Our old Software Trouble Report (STR) system is closed for new reports
since July 2020, as we've transitioned to GitHub Issues for all
You can still post comments to existing STR's
or view the FLTK Roadmap.
To post to our old STR system you need to be logged in as a
registered FLTK user.