Comments: some HTML is stripped from comments on edit

Expected behavior

For any HTML in a comment to remain intact when a comment is created or edited in the mobile app

Actual behavior

While the formatting is applied when viewing the comment in the app and the HTML is visible while editing the comment, the moment the comment is saved, some HTML tags are stripped out. If leaving a comment in the app Reader, some HTML is stripped out immediately on publishing the comment.

Steps to reproduce the behavior

1. Using a browser, comment on a post including a heading and use a span-tag to change some the colour of some text. Example:

<h3 style="padding-left:30px;text-align:center;">Heading</h3>
<span style="color:#eeeeee;"><strong>light grey text</strong></span>
<span style="color:#0000ff;">blue text</span>
<a href="https://wordpress.com/">This is a link</a>

2. In the app, go to W ->Comments and edit the comment. The HTML added in the browser will be visible.

3. Make any edit to the comment and update it. The comment no longer displays some of the formatting:

And on opening it to edit again some of the HTML tags are now missing:

Tested on [device], Android [version]

Confirmed on a Nexus 5X, Android version 8.1.0, App version 9.4

Reported by a user in the WordPress.com forums

Start by reproducing the issue in the Android app using the supplied heading, span, strong, and link HTML, then trace the comment edit and publish flow. Done means the formatting remains intact after saving or publishing, including when the comment is opened for editing again.