The font size of my tooltips doesn't change when you specify a font size in Windows Display options.
The Windows Display Advanced options allow users to specify the visual attributes of most of Windows' components such as Menu font size, icon size, background and foreground colours and the size of the font used in Tooltip text.
The Tooltip option can be found along with the other common components in the drop-down menu in the Advanced section of the Windows Display Appearance dialog. Changing the font size and colour here affects all tooltips on your computer except for those that appear in Windows Explorer. This includes all folder views such as My Documents and My Computer as well as the "common dialog" File Open and Save As dialogs that appear in most Windows programs.
For some reason Windows uses the Icon properties, rather than Tooltip properties, to determine the font size and colour of the Tooltips that appear when looking through files and folders. To adjust the Tooltip font for this area you are forced to simultaneously enlarge your Icon text size. You do this by selecting 'Icon' from the Drop-Down list.
Changing the Icon font size also affects the font that appears on toolbars in Microsoft programs such as Word and Excel.
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