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Uncaught TypeError: Cannot read property 'canvas' of undefined

See original GitHub issue

We have been using waversurferjs to great success (thanks for this awesome library!). 😃 However, it suddenly stopped working and we have no idea why. There were no code changes on our end. It works when run locally on my laptop, but when I deploy to Heroku, we get the error:

vendor-ce0b1d3….js:21 Uncaught TypeError: Cannot read property 'canvas' of undefined
    at Object.updateDimensions (vendor-ce0b1d3….js:21)
    at Object.updateSize (vendor-ce0b1d3….js:21)
    at Object.setWidth (vendor-ce0b1d3….js:21)
    at Object.drawPeaks (vendor-ce0b1d3….js:21)
    at Object.drawBuffer (vendor-ce0b1d3….js:20)
    at Object.loadDecodedBuffer (vendor-ce0b1d3….js:20)
    at Object.<anonymous> (vendor-ce0b1d3….js:20)
    at Object.<anonymous> (vendor-ce0b1d3….js:20)
    at Object.<anonymous> (vendor-ce0b1d3….js:20)
updateDimensions @ vendor-ce0b1d3….js:21
updateSize @ vendor-ce0b1d3….js:21
setWidth @ vendor-ce0b1d3….js:21
drawPeaks @ vendor-ce0b1d3….js:21
drawBuffer @ vendor-ce0b1d3….js:20
loadDecodedBuffer @ vendor-ce0b1d3….js:20
(anonymous) @ vendor-ce0b1d3….js:20
(anonymous) @ vendor-ce0b1d3….js:20
(anonymous) @ vendor-ce0b1d3….js:20

This was working on Heroku last week, and it just stopped working, with no code changes on our our end. However, it still works on our local laptops, it’s only busted when wavesurfer is running inside our Ember app deployed to heroku. waversurfer inside our Ember app deployed to my local laptop works fine.

I have no idea how to debug this … the div it’s supposed to render into is definitely there. Any ideas?

Any help would be hugely appreciated!

Thanks. 😃