OS X 10.10 (Yosemite): Preview fails to keep up with fast window resizing (continued)

Posted by Pierre Igot in: Macintosh
March 9th, 2015 • 1:31 pm

Since my original post about a bug with window resizing in Preview in Yosemite, I have received feedback indicating that not everyone is able to reproduce this bug on their system.

This leads me to suspect that the problem might be limited to specific hardware configurations, like the other responsiveness issues that I have be experiencing since upgrading to Yosemite, which seem to all involve issues of drawing/refreshing the contents of windows, menus, etc. on the screen.

In my original post, I indicated that, in order to reproduce the problem, you really had to use very quick mouse movements in Preview, which will cause it to fail to keep up with your window resizing and only partly resize its contents to fit the frame.

I also indicated that the issue was particularly noticeable when using Keyboard Maestro macros, because these macros effectively mimic very fast mouse movements — in fact faster than what the human hand can achieve.

This means that, while reproducing the problem with a human hand can be challenging, with a Keyboard Maestro macro I am able to reproduce the bug reliably 100% of the time.

So in the interest of further identifying the circumstances under which this Yosemite bug occurs, here is a scenario involving Keyboard Maestro that makes it possible to reproduce the bug without fail:

  1. If you don’t have it yet, download and install Keyboard Maestro on your system.
  2. Create the following macro (or download it here and import it) or a similar one:
  3. km-resize

  4. Open any PDF document in Preview and switch the view mode to “Single Page” (in the “View” menu).
  5. Make the Preview window containing the PDF fairly small.
  6. Execute the macro.

If you have the same bug I have on my system (a 2014 Mac Pro), then the window will resize properly, but Preview will entirely fail to scale the contents to fit the resized window, as it normally should.

The only way to force Preview to scale the contents of the window is to adjust the window size a second time. This will force it to “refresh” the contents and redraw the page at the size it should normally be in a window of that size.

If you can reproduce this bug on your system, I would be very interested to know about it. Please use the link in the sidebar to contact me and send me your hardware configuration.


One Response to “OS X 10.10 (Yosemite): Preview fails to keep up with fast window resizing (continued)”

  1. Betalogue » OS X 10.10.3: Fixes major responsiveness issues on 2014 Mac Pro says:

    […] bug in OS X’s Preview that causes it to fail to keep up with fast window resizing (especially when using a Keyboard Maestro macro) is still […]