Inconsistent icon coloring #171
Description
When the Panorama View button is placed along the tab bar, it can look out of place when a colorful theme is used.
As pictured, the Panorama View button always seems to have a dark-grep color, while the built-in "New Tab" button and Panorama Tab Groups extensions both have a transparency effect.
Ideally, the button icon would follow the same coloring conventions as other icons.