Created attachment 8487367 [details] Screnshot of bug I have GMail set as my email application within Firefox (Tools > Options > Applications > mailto > Use Gmail). When I click on the Email button, I get Gmail loaded within the panel, which is small and constrained. I expected it to open a popup window or another tab. To add to the severity, every time I reopen the panel I see the Gmail compose window. I have to click on Send to close it (there is no Cancel button visible).
[Tracking Requested - why for this release]: This appears to be a pretty severe problem for people who have webmail configured as their default mail application. Loop is scheduled to ship with 34, so it is important that we don't have this usability issue.