Steps to reproduce:

1. Start an Eclipse Che workspace with the default PHP stack and the web-php-simple project template.
2. Start the Apache web server.
3. Enable a PHP debug session in the Che workspace with default settings.
4. Start Firefox.
5. Open the web-php-simple web page.
6. Configure the debug toolbar for Che with Debug Local Copy enabled.
7. Try to debug the current page - it fails.
8. Go to the toolbar settings and disable the Debug Local Copy option.
9. Try to debug again - it fails with "To use the Zend Debugger Toolbar, enable cookie support in your browser."
10. Restart Firefox.
11. Try to debug again - it works!

I use firefox 58.0.2 for osx, after add zend-debugger-toolbar is very good.but i don't know how stop the firefox debug? always debug on next step.

Browser: Firefox 58.0.2 x64 through 60.0
Platform: Kubuntu 17.10 (confirmed also on 18.04)
Extension version: 4.0.1

When using a dark system theme, the Firefox extension's text remains dark, ending up very difficult to read. This is not the case for the rest of Firefox itself. Please note that this is a dark KDE theme (Breeze Dark, which is available as a KDE default), not a dark Firefox theme.

Firefox has dropped support for what they call legacy add-ons. https://support.mozilla.org/en-US/kb/firefox-add-technology-modernizing So the debugger toolbar no longer works: it has been disabled and there is no way to enable it.