made preview tests browser consistent
made preview tests browser consistent

rbecheras/tinymce,TeamupCom/tinymce,blakewallan/tinymce,ikuchmin/tinymce,blakewallan/tinymce,danielpunkass/tinymce,TeamupCom/tinymce,ikuchmin/tinymce,ETSI-CTI/TinySpecMCE,aduth/tinymce,adaptiffdesigns/tinymce,MediehusetTek/tinymce,danielpunkass/tinymce,jtark/tinymce,tinymce/tinymce,danielpunkass/tinymce,fillabs/TinySpecMCE,fillabs/TinySpecMCE,adaptiffdesigns/tinymce,aduth/tinymce,FernCreek/tinymce,tinymce/tinymce,tinymce/tinymce,leofeyer/tinymce,rbecheras/tinymce,jtark/tinymce,leofeyer/tinymce,ETSI-CTI/TinySpecMCE,MediehusetTek/tinymce,FernCreek/tinymce,gencer/tinymce,FernCreek/tinymce,gencer/tinymce