Preferences Dialog is missing What's This? texts

At least Shift-F1 on Linux doesn't change the mouse cursor when I'm in that dialog.

Examples: Preferences -> Text Editors -> Behavior

• Typing -> Tab key performs auto-indent has no help at all (as in: no what's this, no tool-tip, no Help button on the dialog)
• Typing -> Backspace indentation has a tool-tip with what's this-style help text. The problem: tool-tips, unlike what's this texts, disappear after a few seconds. The text, however, is too long to read within that short period of time, requiring the user to move the mouse away, wait, move the moue cursor back and find where he left off before the tooltip diappears again. BTW: the label should be an active area, too, for help.
• File Encodings -> UTF-8 BOM: same, just _even_longer text

Expected: All options have What's This texts (Shift-F1), tooltips are max. one line.