UI fixes / improvements (#12513)

* bbl device selector search box

* align file and more menus with its button

* fix multiline inputbox border color on windows

* fix multiline inputbox border color on windows

* preferences: use content width on combobox dropdowns

* about:  match version text size on macOS

* msg dialog improvements

* fix canvas menu overlapping with sliced plates toolbar

* bbl bind dialog button placement

* bbl color picker

* Update StepMeshDialog.cpp

* drop file dialog

* drop dialog revert fonts

* revert windows multiline border

* Update StepMeshDialog.cpp

* update

* Flushing Volumes: match style of combobox

* fix hyperlink color on canvas notifications

* fix possible issues with shared profiles notification

src/slic3r/GUI/NotificationManager.hpp

@@ -543,6 +543,7 @@ private:
         ImVec4     m_TextColor;
 
 		ImVec4     m_HyperTextColor;
+		ImVec4     m_HyperTextColorHover;
 
         ImVec4     m_ErrorColor;
         ImVec4     m_WarnColor;