improve selection area border
improve selection area border

gyazo/gyazo-browser-extension,modulexcite/gyazo-chrome-extension,3846masa/yabumi-chrome-extension,k725/gyazo-chrome-extension,fkagami/gyazo-chrome-extension,nna774/gyazo-chrome-extension,drobune/gyazo-chrome-extension,gyazo/gyazo-chrome-extension,sekai013/gyazo-chrome-extension,sekai013/gyazo-chrome-extension,uiureo/gyazo-chrome-extension,fkagami/gyazo-chrome-extension,k725/gyazo-chrome-extension,nna774/gyazo-chrome-extension,gyazo/gyazo-chrome-extension,3846masa/yabumi-chrome-extension,gyazo/gyazo-browser-extension,modulexcite/gyazo-chrome-extension,drobune/gyazo-chrome-extension