"Index error: could not find referenced tool name" after adding board URL

Components & Accessories Tools
1

With this list of board URLs:

https://files.pololu.com/arduino/packag … index.json

https://adafruit.github.io/arduino-boar … index.json

https://raw.githubusercontent.com/damel … index.json

I added:

https://raw.githubusercontent.com/spark … index.json

now I get these errors:

Index error: could not find referenced tool name=xtensa-esp32-elf-gcc version=1.22.0-80-g6c4433a-5.2.0 packager=esp32

Index error: could not find referenced tool name=esptool_py version=2.6.1 packager=esp32

Index error: could not find referenced tool name=mkspiffs version=0.2.3 packager=esp32

every time I open “Boards Manager…”

Is there a limit to the number of boards allowed?

Other than the error messages the IDE seems to work OK.

Any suggestions for fixing these errors? Or should I just learn to ignore them?

2

Forgot to add this info:

OS: MacOS 10.15.7

Arduino IDE: 1.8.13

3

It could be that the different board files are conflicting with one another causing the last entry to not install.

Try backing up everything in the boards list, then deleting everything but the last entry.

if that works, add back in the other entries once the last one is installed and running.