Cannot generate post in Wordpress 5 and above

[Ghifari160]

The plugin fails to generate the post in the editor in Wordpress 5 and above (as reported by a user via email).

Wordpress Version: 5.0.3 Logs:

JQMIGRATE: Migrate is installed, version 1.4.1
g16WPIDML.min.js?ver=v0.1:2 [Deprecation] 'webkitURL' is deprecated. Please use 'URL' instead.
(anonymous) @ g16WPIDML.min.js?ver=v0.1:2
3?v=2.0:6 WebSocket connection to 'wss://public-api.wordpress.com/pinghub/wpcom/me/newest-note-data' failed: Error during WebSocket handshake: Unexpected response code: 403
v @ ?v=2.0:6
g16WPIDML.min.js:2 Uncaught TypeError: Cannot read property 'click' of null
    at HTMLButtonElement.next_to_wizardDone (g16WPIDML.min.js:2)
21superpwa-sw.js:50 SuperPWA: Current request is excluded from cache.

[Ghifari160]

Based on the error message Cannot read property 'click' of null, it seems that Wordpress 5 breaks a few Javascript functions. Unfortunately, the plugin ships with a minified version of the Javascript library. A debug cannot be done without reproducing the issue.

Updated ETA: Thursday, February 7, 2019

Current to do list:

• [x] Update toolset to PHP7.3
  • [x] Write a custom Docker image for Apache2 and PHP7.3 on Ubuntu (php7.3-mysql from ppa: ondrej/php returns segmentation fault with any code execution, building PHP from source will be necessary)
  • [x] Update phpMyAdmin Docker image to build from Apache2-PHP7.3 image
  • [x] Update Wordpress Docker image to build from Apache2-PHP7.3 image (ghifari160/apache-php73 needs more PHP extensions to run Wordpress)
• [x] Reproduce issue with a clean instance of Wordpress
• [x] Reproduce issue with dev copy of the plugin
• [ ] Solve issue
• [ ] Release a patch

[Ghifari160]

Bug exists on a clean installation of Wordpress v5.0.3 and Post Generator from IDML v0.1. The client browser is Chrome 71.0.3578.98 (Official Build) (64-bit) (cohort: Stable)

Logs:

JQMIGRATE: Migrate is installed, version 1.4.1
g16WPIDML.min.js?ver=v0.1:2 [Deprecation] 'webkitURL' is deprecated. Please use 'URL' instead.
(anonymous) @ g16WPIDML.min.js?ver=v0.1:2
favicon.ico:1 Failed to load resource: the server responded with a status of 404 (Not Found)
g16WPIDML.min.js?ver=v0.1:2 Uncaught TypeError: Cannot read property 'click' of null
    at HTMLButtonElement.next_to_wizardDone (g16WPIDML.min.js?ver=v0.1:2)

Logs with dev copy:

JQMIGRATE: Migrate is installed, version 1.4.1
g16WPIDML.dev.js?ver=v0.1:43 [Deprecation] 'webkitURL' is deprecated. Please use 'URL' instead.
(anonymous) @ g16WPIDML.dev.js?ver=v0.1:43
(anonymous) @ g16WPIDML.dev.js?ver=v0.1:85
(anonymous) @ g16WPIDML.dev.js?ver=v0.1:450
g16WPIDML.dev.js?ver=v0.1:253 Uncaught TypeError: Cannot read property 'click' of null
    at HTMLButtonElement.next_to_wizardDone (g16WPIDML.dev.js?ver=v0.1:253)