How to change the theme Microsoft Edge, including Reading View Style
Microsoft Edge offers a choice of two display themes:
Step 1
Open a web page and the default Light theme will be selected. This is applied to all displayed menus, for example, History, below:
Step 2
From More Options (…) > Settings, pick Dark from the Choose a theme drop-down
Reading View Style
More Options > Settings > Reading offers four view styles: the Default, plus Light, Medium and Dark.
Step 1
Click the Reading view style from the drop-down menu, and select Medium
You can switch to the high contrast Dark theme if it makes it easier for you to view web pages.

Reading view also offers a choice of font size – Small, Medium (the default), Large and Extra Large.
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