Unintended consequence of custom separator?

Problem/Motivation

The separator config appears to be applied too liberally? This can result in malformed metatags and schema metadata.

The separator config is managed at: /admin/config/search/metatag/settings

This issue appears to have been originally identified on Mar 26, 2021, but may have been overlooked.

Steps to reproduce

Case 1: Robots.txt > Invalid Markup
Set the separator config to a pipe (|).

Override contents of robots.txt in a node and observe the invalid rendering of the

<meta name="robots" content="index| follow| max-snippet:160| max-image-preview:large" />

Interestingly, it appears that the default checkboxes for these may also be lost when the separator is applied?

Case 2: Schema.org > Unexpected Array

Use the default separator config of a comma (,).

Schema (use Review and set the reviewBody to a field that includes text that includes commas (like a paragraph of text that includes commas). Then observe the reviewBody is now set to an array.

I suspect there may be other unintentional side-effects, but that's unclear.

Proposed resolution

TBD

Remaining tasks

Identify root cause. Evaluate potential places were use of separator config might be restricted or otherwise revisited.

User interface changes

TBD

API changes

TBD

Data model changes

TBD