This is an FYI.
Converting from 5.0.10 to 6.5. Have several actions that appear in the action bar of forms in 5.0.10. These actions do not contain an icon, only text. Whne th form is displayed in 6.5 these icons show up only on mouse over and a single line. Removed the check in action properties - only show icon in action bar. Now the single letter shows as it did in 5.0.10.