1) Start Nightly 2) Load https://bugzilla.mozilla.org 3) Open devtools / debugger 4) Select global.js 5) Right-click line 20ish (first line inside first function) *on the line number* and choose "Add conditional breakpoint" On mouse*down* a breakpoint appears on line 20. When choosing the menu entry, a breakpoint appears on line 1 (which is a comment and can't take breakpoints). Unsurprisingly, this breakpoint never triggers.. Side effect: trying to set a conditional breakpoint on some other line will just go into "editing mode" for the breakpoint on line 1.

Reproduced on Linux, too. This is weird.

Hm.. might be considered a dup of bug 813180. But if it's a known issue that the feature doesn't work when right-clicking the gutter, and making it work is hard (?!?) we should perhaps not invoke the right-click menu at all when line numbers are clicked..?

Bug 986151 will clear some of the confusion here, but not all of it.

Bug 986151 evolved into a duplicate of this bug. It will be fixed once that patch lands.