ReadingRuler

Tracking since Apr 1, 2026.

Changelog

• Apr 30, 2026
  description

  Based on this script:
  https://greasyfork.org/en/scripts/372448-reading-ruler/code
  
  This reading ruler will aid you on reading texts on the internet
  It will place a semi-transparent line on your screen, just hit the combination ctrl + r on windows and mac (not the command button but the control button) to activate the ruler, hit the same configuration to remove the ruler
  
  This idea come from the reddit user /u/VectorLightning
  And the thread can be found here: https://www.reddit.com/r/SomebodyMakeThis/comments/9huwbw/smt_a_firefox_addon_that_adds_a_horizontal/
  
  I hope you find this extension useful
  
  Releases Notes:
  V4.0
  Redo of the extension, all the features introduced on V3.1 were causing a lot of bug, surprisingly there are still people using and finding this extension, so I decided to simplify it and make it work on all websites. I hope this update fixes all major issues reported on the feedback page.
  
  Here a list of changes:
  - You are not able to set a shortcut anymore, for now these are set by default.
    - Windows: ALT + SHIFT + 3
    - Mac: Command + SHIFT + U
  - Color and opacity are still options that you can change
  - Add save button to apply changes done to the ruler color and opacity
  - Fix issue with ruler not working on multiple websites
  - Simplified core mechanism to allow extension to always work
  
  
  V3.1
  Lots of improvements, extension should now always work and should not be invisible
  
  - fix problem where ruler would not show on screen (for real this time!)
  - new popup layout with 2 new options
    - you now can choose a color for your ruler
    - you can now set how visible you want your ruler to be
  - update core code
    - remove itself when its orphaned
    - create functions to prevent references on event handlers
    - remove unnecessary calls to background script
    - overall improve code to work better
  
  v3.0.1
  - Avoid exceptions when extension is updated
  - Increase z index of ruler to try to push to the foreground
  
  v3.0
  - Code rewrite to make extension function properly
  - Update manifest to V3
  - Fix extension so it should only show the ruler when active
  - Drop support for Alt modifier key, you can now only combine CTRL, SHIFT and a keyboard key
  - Drop badge text since it was not working anymore
  
  v 2.2
  - Fix issue with ruler not showing when pressing the toggle combination
  
  v 2.1
  - Add badge to extension icon to let you know the tool is active
  
  v 2.0
  - Add options page
    - Allow user to choose from using CTRL, ALT and SHIFT plus a key
  - Update and rewrite the entire code to be more OOP

  Based on this script:
  https://greasyfork.org/en/scripts/372448-reading-ruler/code
  
  This reading ruler will aid you on reading texts on the internet
  It will place a semi-transparent line on your screen, just hit the combination ctrl + r on windows and mac (not the command button but the control button) to activate the ruler, hit the same configuration to remove the ruler
  
  This idea come from the reddit user /u/VectorLightning
  And the thread can be found here: https://www.reddit.com/r/SomebodyMakeThis/comments/9huwbw/smt_a_firefox_addon_that_adds_a_horizontal/
  
  I hope you find this extension useful
  
  Releases Notes:
  V4.1
  Bug fixes
    - Fixed the keyboard shortcut not working. The root cause was a race condition in the background service worker settings hadn't finished loading from storage when the shortcut was pressed, causing a silent crash that prevented the ruler from ever appearing.
    - Fixed the extension not working on tabs that were already open before the extension was installed or updated. The content script is now injected on-demand when needed, so there is no longer a need to reload existing tabs.
    - Fixed ruler opacity not saving correctly - the value from the slider was being stored as a string instead of a number.
    - Fixed a background script security issue where the message handler could invoke arbitrary functions.
  
    UI
    - Redesigned the popup with a clean, minimal layout
    - Keyboard shortcuts are now displayed with proper kbd key styling.
    - Opacity slider now shows the current value as you drag it.
    - Save button gives visual confirmation when settings are saved.                                                         
    - Removed all external dependencies (Bootstrap, jQuery, Google Fonts, bootstrap-toggle) - the popup no longer requires an internet connection to render correctly and loads instantly.  
  
  V4.0
  Redo of the extension, all the features introduced on V3.1 were causing a lot of bug, surprisingly there are still people using and finding this extension, so I decided to simplify it and make it work on all websites. I hope this update fixes all major issues reported on the feedback page.
  
  Here a list of changes:
  - You are not able to set a shortcut anymore, for now these are set by default.
    - Windows: ALT + SHIFT + 3
    - Mac: Command + SHIFT + U
  - Color and opacity are still options that you can change
  - Add save button to apply changes done to the ruler color and opacity
  - Fix issue with ruler not working on multiple websites
  - Simplified core mechanism to allow extension to always work
  
  
  V3.1
  Lots of improvements, extension should now always work and should not be invisible
  
  - fix problem where ruler would not show on screen (for real this time!)
  - new popup layout with 2 new options
    - you now can choose a color for your ruler
    - you can now set how visible you want your ruler to be
  - update core code
    - remove itself when its orphaned
    - create functions to prevent references on event handlers
    - remove unnecessary calls to background script
    - overall improve code to work better
  
  v3.0.1
  - Avoid exceptions when extension is updated
  - Increase z index of ruler to try to push to the foreground
  
  v3.0
  - Code rewrite to make extension function properly
  - Update manifest to V3
  - Fix extension so it should only show the ruler when active
  - Drop support for Alt modifier key, you can now only combine CTRL, SHIFT and a keyboard key
  - Drop badge text since it was not working anymore
  
  v 2.2
  - Fix issue with ruler not showing when pressing the toggle combination
  
  v 2.1
  - Add badge to extension icon to let you know the tool is active
  
  v 2.0
  - Add options page
    - Allow user to choose from using CTRL, ALT and SHIFT plus a key
  - Update and rewrite the entire code to be more OOP

• Apr 30, 2026
  short_description

  A reading aid for pages with wiiiiiiide paragraphs.

  A reading aid that highlights the line you are reading.

• Apr 30, 2026
  permissions

  storage, activeTab

  storage, activeTab, scripting

Permissions & access

Permissions

storageactiveTabscripting

Host access

None declared

Screenshots

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