diff --git a/docs/faq_build.md b/docs/faq_build.md
index bcf017a9b2..3fe358edaf 100644
--- a/docs/faq_build.md
+++ b/docs/faq_build.md
@@ -19,7 +19,11 @@ Note that running `make` with `sudo` is generally ***not*** a good idea, and you
 
 ### Linux `udev` Rules
 On Linux, you'll need proper privileges to access the MCU. You can either use
-`sudo` when flashing firmware, or place these files in `/etc/udev/rules.d/`.
+`sudo` when flashing firmware, or place these files in `/etc/udev/rules.d/`. Once added run the following:
+```console
+sudo udevadm control --reload-rules
+sudo udevadm trigger
+```
 
 **/etc/udev/rules.d/50-atmel-dfu.rules:**
 ```
@@ -43,6 +47,28 @@ SUBSYSTEMS=="usb", ATTRS{idVendor}=="feed", MODE:="0666"
 SUBSYSTEMS=="usb", ATTRS{idVendor}=="1c11", MODE:="0666"
 ```
 
+**/etc/udev/rules.d/55-catalina.rules:**
+```
+# ModemManager should ignore the following devices
+ATTRS{idVendor}=="2a03", ENV{ID_MM_DEVICE_IGNORE}="1"
+ATTRS{idVendor}=="2341", ENV{ID_MM_DEVICE_IGNORE}="1"
+```
+
+**Note:** ModemManager filtering only works when not in strict mode, the following commands can update that settings:
+```console
+sudo sed -i 's/--filter-policy=strict/--filter-policy=default/' /lib/systemd/system/ModemManager.service
+sudo systemctl daemon-reload
+sudo systemctl restart ModemManager
+```
+
+**/etc/udev/rules.d/56-dfu-util.rules:**
+```
+# stm32duino
+SUBSYSTEMS=="usb", ATTRS{idVendor}=="1eaf", ATTRS{idProduct}=="0003", MODE:="0666"
+# Generic stm32
+SUBSYSTEMS=="usb", ATTRS{idVendor}=="0483", ATTRS{idProduct}=="df11", MODE:="0666"
+```
+
 ### Serial device is not detected in bootloader mode on Linux
 Make sure your kernel has appropriate support for your device. If your device uses USB ACM, such as
 Pro Micro (Atmega32u4), make sure to include `CONFIG_USB_ACM=y`. Other devices may require `USB_SERIAL` and any of its sub options.