If you ever have to do that again it might be worth considering some hardware assistance. An ESP32 S2 or S3, from what I've read, can act as a USB HID and emula

If you ever have to do that again it might be worth considering some hardware assistance. An ESP32 S2 or S3, from what I've read, can act as a USB HID and emulate a keyboard from the computer's point of view. The necessary code is included in the ESP32 libraries for Arduino, with examples [1], so for software all you'd need is the Arduino IDE or command line tools, which run fine on Linux. With that it would be easy to build a temporary "type my secret key" dongle. An ESP32 S2 or S3 dev kit board from a reputable source along with the other necessary hardware would probably be under $20. There are also some models of Arduino that have the necessary USB support such as the Arduino Leonardo [2], but the Leonardo is more than an EPS32 at the non-sketchy sellers I've seen. Even if you've never played around with microcontrollers this would be a beginner level project. [1] https://github.com/espressif/arduino-esp32/tree/master/libraries/USB/examples https://github.com/espressif/arduino-esp32/tree/master/libra... [2] https://docs.arduino.cc/hardware/leonardo/ https://docs.arduino.cc/hardware/leonardo/