运维中心查到的错误内容如下，相关代码里没有用到 indexOf

报错的位置 https://lib/WASubContext.js:2:408172 这种文件是小程序内置的代码吗？有办法查到具体报错的位置吗？

Cannot read property 'indexOf' of undefined; [Component] Event Listener Error @ frameBase/components/canvas-to-image/canvas-to-image#(anonymous)
TypeError: Cannot read property 'indexOf' of undefined
at g (https://lib/WASubContext.js:2:408172)
at Ae (https://lib/WASubContext.js:2:627116)
at i.Me.<computed> [as drawImage] (https://lib/WASubContext.js:2:637700)
at i.p.<computed> [as drawImage] (https://lib/WASubContext.js:2:1236535)
at be.canvasDraw (https://usr//pages/produce/app-service.js:4120:4173)
at be.B.d.<computed>.<computed>.d.addListener.capture (https://lib/WASubContext.js:2:1473055)
at r.safeCallback (https://lib/WASubContext.js:2:1243366)
at r.call (https://lib/WASubContext.js:2:1243259)
at o (https://lib/WASubContext.js:2:1246663)
at https://lib/WASubContext.js:2:1247404