Newline characters in selections can appear in link titles

[wheelercj]

Describe the bug
With the "When creating markdown of a selection, create a link with the selected text as the title" setting, if multiple unordered list items of text are selected and the "Copy markdown of selection" context menu option is used, the resulting markdown link will have a newline character in it, which breaks the markdown syntax of the link.

To Reproduce
Steps to reproduce the behavior:

1. Go to https://en.wikipedia.org/wiki/Main_Page
2. Select multiple items in an unordered list
3. Right-click the selection and choose "Copy markdown of selection"
4. Paste the markdown
5. See that the pasted markdown spans multiple lines, and so is not a valid markdown link.

Expected behavior
The newline characters should be removed, maybe replaced with spaces.

Environment

• Browser: all