The file https://files.seeedstudio.com/arduino/package_seeeduino_boards_index.json
is not served correctly at the moment. Meaning it only returns part of the json file, which means that the
parsing in Arduion IDE will fail and result on the board not beeing added to the arduino IDE.
It can easily be tested by going to https://files.seeedstudio.com/arduino/package_seeeduino_boards_index.json in the browser and scroll to the bottom of the response.
I have exactly the same problem. The file is incomplete, I can no longer work with my Seeeduino Xiaos. 
Same here… Does anyone have an older version of the file so we can at least use our boards until its fixed?
Same here. Dead in the water. Someone needs to improve their testing practices.
Same! Signed up for an account just to report this.
I have same problem！！
Sorry, this problem should have occurred when the product was optimized yesterday. At present, the R&D department has received feedback and is stepping up to fix the problem. It should be solved within today, causing inconvenience to everyone.
Same problem here! I was in the middle of a project development.
I hope the issue gets solved ASAP
Does anyone have a temporary solution to propose? I am thinking of feeding a working file to the Arduino IDE to make the Xiao board re-appear (like @Stefan suggested) or something along that line.
I am sorry if I am talking non sense, I am a newbie. Thank you all.
never thought I’d need to back up this particular file. I hope this fixed soon because my work is hosted until that happens.
Skipping contributed index file /home/bottledlunatic/.arduino15/package_seeeduino_boards_index.json, parsing error occured:
com.fasterxml.jackson.databind.JsonMappingException: Unexpected end-of-input within/between Object entries
at [Source: (FileInputStream); line: 3805, column: 1304]
at [Source: (FileInputStream); line: 3804, column: 26] (through reference chain: cc.arduino.contributions.packages.ContributionsIndex[“packages”]->java.util.ArrayList[0]->cc.arduino.contributions.packages.ContributedPackage[“tools”]->java.util.ArrayList[47]->cc.arduino.contributions.packages.ContributedTool[“systems”]->java.util.ArrayList[3])
Skipping contributed index file /home/bottledlunatic/.arduino15/package_seeeduino_boards_index.json, parsing error occured:
com.fasterxml.jackson.databind.JsonMappingException: Unexpected end-of-input within/between Object entries
at [Source: (FileInputStream); line: 3805, column: 1304]
at [Source: (FileInputStream); line: 3804, column: 26] (through reference chain: cc.arduino.contributions.packages.ContributionsIndex[“packages”]->java.util.ArrayList[0]->cc.arduino.contributions.packages.ContributedPackage[“tools”]->java.util.ArrayList[47]->cc.arduino.contributions.packages.ContributedTool[“systems”]->java.util.ArrayList[3])
repaired. Everything works, thank you!!!
