document.registerElement is deprecated and will be removed from Chrome in March 2019

[sebastianbk]

First of all, thank you so much for sharing this project. I am absolutely in love with Facets and so grateful for all of the work you have put into this.

I am making use of Facets in a customer-facing SaaS app and I have noticed a warning that I am getting the Chrome developer console. See below:

[Deprecation] document.registerElement is deprecated and will be removed in M73, around March 2019.
Please use window.customElements.define instead.
See https://www.chromestatus.com/features/4642138092470272 for more details.

I am making use of the compiled "package" of Facets (the facets-jupyter.html file), which apparently makes use of the document.registerElement API. Would it be possible to refactor the part of Facets that makes use of this API so that we won't run into problems when M73 is released?

[jameswex]

Thanks for the support and the issue report. We plan on upgrading Facets from Polymer 1 to Polymer 2 which should eliminate this issue. Work on that will probably be done in February. Note that the registerElement removal webpage now points to April instead of March.

[sebastianbk]

@jameswex: Thanks for the quick response. I will leave this issue open until you release the new version in February. I'll verify the fix and then close this thread.

Have an amazing day! 😃

[sebastianbk]

Hi @jameswex

How is it going with the upgrade to Polymer 2?

We run Facets Dive in production and I would really like to make sure that our customers aren’t experiencing any disruptions. Is there something that I can do to help with the upgrade effort?

[jameswex]

The Polymer update for Facets is in-progress. It first requires a Polymer 2 update in the TensorBoard repository, since Facets uses TensorBoard's bazel build/workspace rules, including its Polymer stuff. That is actively being worked on.

The good news is that Facets will not fail starting in Chrome M73 (the warning is strangely worded I would say). Polymer 1.0 elements in Chrome M73 will start to function just as they already do on other browsers, using polyfills to get their functionality.

For a preview of how your app will run on Chrome 73, you can start Chrome with these command-line flags: --disable-blink-features=ShadowDOMV0,CustomElementsV0,HTMLImports

You should still see Facets running correctly. If not, then you would just need to add the polyfill loading to your webapp (https://www.webcomponents.org/polyfills)