Confusing error message when trying to insert inline comment in macro content

Issue Summary

If you create and try to save an inline comment after highlighting the text in a Summary field contained within a Jira Issues macro, Confluence returns the message "Could not save the comment."

Environment

• Occurred in Confluence version 6.15.1, verified in version 6.13.0 with Jira 7.13.0

Steps to Reproduce

1. Create an app link integration between Confluence and Jira.
2. Create a page in Confluence.
3. Add a Jira Issues macro into the page. When configuring the display of the macro, ensure that the Summary field is included.
4. Save the page.
5. View the page in Confluence.
6. Highlight text located within the Summary column and click on inline comment icon to add a comment.
7. Enter comment and save.

Expected Results

You are prevented from using inline comments on the output of a macro and get an error message stating that.

Actual Results

Confluence returns the message "Could not save the comment."

HAR file shows that the following REST call returns an HTTP 500 error:

<base-url>/rest/inlinecomments/1.0/comments

Application logs show the following error:

2019-04-18 09:52:27,093 WARN [http-nio-9613-exec-7] [plugins.inlinecomments.service.InlineCommentServiceImpl] attemptInlineCommentCreateForPage The text selection is wrong
 -- referer: <base-url>/display/MYSPACE/Test+Page | url: /conf/rest/inlinecomments/1.0/comments | traceId: 832de33c025e7082 | userName: charlie
com.atlassian.confluence.plugins.highlight.SelectionModificationException: The text selection is wrong
	at com.atlassian.confluence.plugins.highlight.service.SelectionValidator.validateSelection(SelectionValidator.java:65)

Workaround

None. Not being able to highlight text and add an inline comment is by design.