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Preview of Reading Ruler – Line Focus Guide

Reading Ruler – Line Focus Guide by Lakeside Apps

A colored strip follows your mouse on any website and helps you keep your place in long text. Pro adds a focus mask.

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About this extension
Reading Ruler puts a soft colored strip across the screen that moves with your mouse. It marks where you are, so the eyes find the next line without jumping too far. It helps keep your place while reading long articles, documents and emails. The free version has no limit and needs no account. Pro costs $5.99 once, no subscription.

WHAT IT DOES
The ruler sits on top of the website and never blocks it: links, text selection and scrolling keep working. Choose a wide band or a thin underline and set the height to one or two lines. It also stays visible in fullscreen and on sites that rebuild themselves while you scroll.

HOW IT WORKS
1. Open any website.
2. Click the toolbar icon and press "Turn on for this page", or press Alt+Shift+L.
3. Move the mouse down the text. Esc turns it off again.

FREE
• The band or underline on any regular website, without a limit.
• Height from a thin line up to several lines of text.
• A keyboard shortcut to turn it on and off.

PRO ($5.99, LIFETIME)
• Focus mask: everything above and below the current line is dimmed, with adjustable darkness.
• Six tints and an opacity slider.
• Always on for the sites you choose, so it starts by itself there.
• Keyboard stepping: Alt and the arrow keys move the ruler one line at a time.

PRIVACY
The extension only draws on the tab you turn it on for. It does not read, store or send the text of any page. Settings stay in your browser. The only data sent anywhere is the email you enter to buy or restore Pro, which is checked against the payment.

Questions: scanlystudio.support@proton.me
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Version
1.0.0
Size
157.45 KB
Last updated
8 days ago (Oct 27, 2026)
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