Dialog box message not copiable if contains \n character

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Describe your context
Usign Dash for a Jira REST API Client, need to have a dynamic confirmDialog

• replace the result of pip list | grep dash below

dash                  1.19.0
dash-core-components  1.15.0
dash-html-components  1.1.2
dash-renderer         1.9.0
dash-table            4.11.2

• if frontend related, tell us your Browser, Version and OS

  • OS: ubuntu18.04
  • Browser chrome
  • Version 89

Describe the bug

When setting message value of dcc.ConfirmDialog if a \n character is present the message text can't be copied, works if no \n is present

Expected behavior

We wanted to have a list of issue keys in the dialog box to be copied, but the text can't be copied if it has a \n character in it

Start at the dcc.ConfirmDialog component and reproduce the issue with a message containing a newline in Chrome on Ubuntu. Check how the dialog renders and exposes its text, then verify that a list of issue keys can be selected and copied when the message includes newline characters.