This commit fixes 2 issues specific to the firefox version of the extension:
First issue concerns the computation the position of the border between the subwindows of the components tab which could go terribly wrong due to the fact that the innerwidth of the window is implicitly set to 10 when the owl devtools window is hidden. Second issue comes from changes in the runtime.onMessage method of browser which now requires to directly return the response instead of using the sendResponse method.
Also perform a little cleanup on usage of browserInstance and in the manifest.
This commit fixes 2 issues specific to the firefox version of the extension: First issue concerns the computation the position of the border between the subwindows of the components tab which could go terribly wrong due to the fact that the innerwidth of the window is implicitly set to 10 when the owl devtools window is hidden. Second issue comes from changes in the runtime.onMessage method of browser which now requires to directly return the response instead of using the sendResponse method. Also perform a little cleanup on usage of browserInstance and in the manifest.