[Bug] Mousekeys in Constant Speed Mode only move one step per keypress

Describe the Bug

I have a problem when using the constant speed mode with mouse keys in that when I press and hold one of the mouse direction buttons the cursor only moves one step and stops afterwards. I would have expected the cursor to keep moving while holding the keypress. Is this a bug or intended behavior?

For the setup I just followed the instructions on the docs page for mouse keys. And other mouse modes work without issue.

I use a Lily58 rev1 on Ubuntu 20.04., but the issue also persists when I connect the keyboard to my Laptop which runs MacOs.

qmk version: 1.1.0

System Information

Keyboard: Lily58 Revision (if applicable): rev1 Operating system: Ubuntu 20.04. qmk doctor output:

Ψ QMK Doctor is checking your environment.
Ψ CLI version: 1.1.0
Ψ QMK home: <obscured>/qmk_firmware
Ψ Detected Linux.
⚠ Missing or outdated udev rules for 'atmel-dfu' boards. Run 'sudo cp <obscured>/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'kiibohd' boards. Run 'sudo cp <obscured>/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'stm32' boards. Run 'sudo cp <obscured>/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'bootloadhid' boards. Run 'sudo cp <obscured>/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'usbasploader' boards. Run 'sudo cp <obscured>/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'massdrop' boards. Run 'sudo cp <obscured>/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Detected ModemManager without the necessary udev rules. Please either disable it or set the appropriate udev rules if you are using a Pro Micro.
⚠ Missing or outdated udev rules for 'caterina' boards. Run 'sudo cp <obscured>/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'hid-bootloader' boards. Run 'sudo cp <obscured>/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
Ψ Git branch: master
Ψ Repo version: 0.17.0
Ψ All dependencies are installed.
Ψ Found arm-none-eabi-gcc version 9.2.1
Ψ Found avr-gcc version 5.4.0
Ψ Found avrdude version 6.3-20171130
Ψ Found dfu-util version 0.9
Ψ Found dfu-programmer version 0.6.1
Ψ Submodules are up to date.
Ψ QMK is ready to go, but minor problems were found

Any keyboard related software installed?

• AutoHotKey (Windows)
• Karabiner (macOS)
• Other: None

Additional Context