Providing information on crashes
In general
Please create a bug report on: https://sourceforge.net/p/bluefish/tickets/
Or subscribe to the bluefish community mailinglist.
If this is all too complicated you can send an email to bluefish@bluefish.openoffice.nl
Linux
OSX
If Bluefish crashes on OSX there should be report generated in separate window. Please copy/paste this information (the backtrace) for thread 0 (on the top of the report) to text file and send it to the bluefish developers. Preferably create a bug report on https://sourceforge.net/p/bluefish/tickets/ and attach it as a text file.
On OSX you can run Bluefish via terminal, that provides some debug output that might help to identify issue. Open terminal and type: /Applications/Bluefish.app/Contents/MacOS/bluefish (assuming that Bluefish is installed in the Applications folder). Please copy/paste the terminal output to a text file and attach it as well.