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What's It For?
Set a different pixel ratio (layout.css.devPixelsPerPx) for each of your screens. Useful for mixed-DPI multi-monitor setups. For example, you can use it if you have one HiDPI (Retina) screen and one lower-DPI HD screen.
How It Works?
First, you set a pixel ratio for your current screen using the toolbar button. You can set pixel ratios for any number of screens. Whenever the active window is moved to another screen, it automatically scales the window contents, including the user interface, to match the active screen DPI.
- 3.0.1: Screen width based activation method is replaced with a screen geometry based approach that allows setting custom pixel ratios for each screen. Add-on preferences are now available through the toolbar button. If you have existing settings from previous versions, they will be preserved in a backward compatible manner.
Limitations & Known Bugs
- Probably, it's only needed on Linux and it's only tested on Linux.
- You shouldn't use the zoom function of Firefox because it affects the reported screen resolution and the current screen becomes a new unknown screen for AutoHiDPI due to the changed screen geometry.
- Pixel ratio (devPixelsPerPx) is a global setting in Firefox, therefore if you have multiple windows open that are spanning screens with differing DPIs, all the windows will be scaled according to the pixel ratio of the screen containing the active window.
- When you change your screen geometry (i.e. add or remove screens), Firefox sometimes report the screen geometry incorrectly and it may cause problems with AutoHiDPI. The workaround is restarting Firefox.
Reporting Issues & Source Code
You can report issues here. Source code is available at GitHub, pull requests are welcome!
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