On what seems to be random occasions, when a user on my website tries to answer a question on the quiz page, the following error occurs:
TypeError: Cannot read property 'invalidate' of undefined at Tracker.Dependency.changed (tracker.js:388) at ReactiveVar.set (reactive-var.js:82) at null. (builtins.js:22) at view.js:191 at Function.Template._withTemplateInstanceFunc (template.js:437) at view.js:190 at Object.Blaze._withCurrentView (view.js:523) at viewAutorun (view.js:189) at Tracker.Computation._compute (tracker.js:294) at Tracker.Computation._recompute (tracker.js:313)
When the error is present, the current template SOMETIMES doesn’t render properly (when a user answers a question, the answer they clicked either turns red if incorrect, or green if correct). More often than not, the template renders fine with the updated inserted classes (reactive template with handlebars). I don’t know why this occurs, and I am not entirely sure what this error even means so if someone could point me in the right direction, that would be great!
Note: this error seems to only occur when using Chrome. Here’s a link to the post i put up on the Meteor github page. Another user has run into this problem too. In Firefox, the following warning gets displayed:
mutating the [[Prototype]] of an object will cause your code to run very slowly; instead create the object with the correct initial [[Prototype]] value using Object.create
but oddly enough, the page renders fine, unlike in Chrome.