Update faq.rst (esphome#2057)

Author: Weldawadyathink

guides/faq.rst

@@ -364,7 +364,7 @@ If an external pullup/down changes the configured voltage levels boot failures o
 While the use of them in software is not a problem, if there's something attached to the pins (particularly if they're not floating during the bootup) you may run into problems.
 It's recommended to avoid them unless you have a pressing need to use them and you have reviewed the expected boot voltage levels of these pins from the ESP datasheet.
 
-Note that some boards connect pins such as GPIO0 to a builtin tactile switch. In these cases using the strapping pins is not a problem.
+Some development boards connect GPIO 0 to a button, often labeled "boot". Holding this button while the ESP is turning on will cause it to go into bootloader mode. Once the ESP is fully booted up, this button can be used as a normal input safely. 
 
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