TypeError [ERR_INVALID_ARG_TYPE]: The "file" argument must be of type string. Received type object

[fangx4]

wget http://127.0.0.1:8891/?url=github.com -O github.png

--2020-09-28 15:04:32-- http://127.0.0.1:8891/?url=github.com
Connecting to 127.0.0.1:8891... connected.
HTTP request sent, awaiting response... 2020-09-28T07:04:32.288Z - info: Capture site screenshot: "github.com"
2020-09-28T07:04:32.745Z - error: Process error: internal/validators.js:125
throw new ERR_INVALID_ARG_TYPE(name, 'string', value);
^

TypeError [ERR_INVALID_ARG_TYPE]: The "file" argument must be of type string. Received type object
at validateString (internal/validators.js:125:11)
at normalizeSpawnArguments (child_process.js:411:3)
at spawn (child_process.js:545:16)
at Object. (/usr/local/lib/node_modules/phantomjs/bin/phantomjs:22:10)
at Module._compile (internal/modules/cjs/loader.js:778:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:789:10)
at Module.load (internal/modules/cjs/loader.js:653:32)
at tryModuleLoad (internal/modules/cjs/loader.js:593:12)
at Function.Module._load (internal/modules/cjs/loader.js:585:3)
at Function.Module.runMain (internal/modules/cjs/loader.js:831:12)

2020-09-28T07:04:32.745Z - error: error=Can not capture: github.com
500 Internal Server Error
2020-09-28 15:04:32 ERROR 500: Internal Server Error.