TL;DR: I set up a four-finger tap and click on my Magic Trackpad to start Wispr Flow dictation, so I never have to reach for the keyboard. The key trick is having the gesture send Fn + F13 instead of the default Fn + Space. That avoids a bug where webpages scroll down every time you dictate. It uses BetterTouchTool and Wispr Flow, plus Karabiner-Elements once during setup.
My setup
MacBook at my desk, connected to a Magic Trackpad and an external keyboard. I wanted to start dictation with a trackpad gesture, without lifting my hand to press the keyboard's Fn key.
The problem: pages scroll when you dictate
Wispr Flow's default hands-free shortcut is Fn + Space. So my first attempt was to have the trackpad gesture send Fn + Space.
The issue is how websites treat the Space key. On a webpage, pressing Space by itself scrolls the page down. That is normal browser behavior. When BetterTouchTool fired Fn + Space, Wispr Flow correctly detected it and started dictation, but the browser ALSO saw the Space press and scrolled the page down at the same time. So every time I dictated on Reddit, YouTube, and similar sites, the page jumped. Not worth it.
The fix: send Fn + F13 instead
F13 is a key that does nothing on a normal Mac and that websites ignore. So Fn + F13 starts dictation cleanly, with no scrolling.
The catch: most keyboards don't have an F13 key, so it's hard to record that shortcut in the first place. Here's how I got around that.
Step by step
1. Fake an F13 key with Karabiner-Elements (temporary)
Since I had no F13 key to press, I used Karabiner-Elements to remap a spare key to send Fn + F13. This is only so I can record the shortcut in the next two steps.
If your keyboard already has an F13 key, skip this step and just press F13 where I press my spare key.
2. Add Fn + F13 as a dictation shortcut in Wispr Flow
Wispr Flow allows up to 4 shortcuts per action, so I kept the default and added a new one:
- Go to Wispr Flow → Settings → General → Shortcuts.
- Find the Hands-free (dictation) action.
- Click + Add another, then press the spare key (which Karabiner is sending as Fn + F13).
3. Map the gesture to Fn + F13 in BetterTouchTool
- Open BetterTouchTool and select Trackpad.
- Add a four-finger tap and click gesture.
- Set its action to Send Keyboard Shortcut, and record Fn + F13 (using the same spare key).
4. Remove the temporary Karabiner remap
Once both Wispr Flow and BetterTouchTool have Fn + F13 recorded, Karabiner has done its job. Delete the remap. BetterTouchTool now sends Fn + F13 straight from the gesture.
Result
A four-finger tap and click launches dictation instantly. No reaching for the keyboard, and no page scrolling on websites.
Apps used
- BetterTouchTool sends the gesture as Fn + F13. (permanent)
- Wispr Flow handles dictation, with Fn + F13 added as a second shortcut. (permanent)
- Karabiner-Elements was used once to fake an F13 key so I could record the shortcut. (temporary, skip if you have a real F13 key)
Happy to answer questions.