Boot key does not set Teensy 4.1 to bootloader mode in custom firmware

[sockbot]

When I use the default firmware on a Teensy 4.1, the mapped boot key sets the Teensy into bootloader mode.

When I compile a custom firmware with the configurator at https://config.qmk.fm/#/kinesis/kint41/LAYOUT pressing the boot key makes the Teensy and the keyboard unresponsive until power cycled.

To reproduce, compile this keyboard layout and press the boot key:

kinesis_kint41_layout_2025-09-08.json

[sockbot]

Symptoms may be related to this issue #77

[stapelberg]

Is this a duplicate of issue #80?

[sockbot]

I'm not sure how to duplicate #80. I'm using teensy_loader_cli -- how do I see the state of the Teensy? I'm just going to try the fix in #77 to use an older version of qmk as a workaround.

[echristophe]

I was running into both #80 and #88 and using the rejected pull request mentioned in #80 https://github.com/qmk/qmk_firmware/pull/23054/files fixed both issues.

[sockbot]

I was able to work around this issue by checking out the issue-23053 branch here https://github.com/stevenbetten/qmk_firmware/tree/issue-23053 and using it to compile the firmware.

I note the qmk documentation failed to install all of the dependencies on Arch so some manual work is required, but it worked in the end.

[stapelberg]

Let’s keep this issue open for visibility until it’s fixed in QMK upstream.

[sockbot]

A workaround PR for this issue was submitted to the qmk project and was rejected by a qmk member.

qmk/qmk_firmware#23054 (comment)

They believe the issue need to be resolved at the ChibiOS level.