Currently when you wish to include only parts of an issue description as a quote in a comment, you have two options:
a) use the quote button for the issue description and delete all unnecessary description from the quote
b) manually highlight parts of the issue description, add a new comment and copy+paste the hightlighted parts

Both options have their obvious disadvantages:
a) especially with lengthy issue descriptions it can be tedious work to manually delete text in the small comment edit text field
b) all formatting is lost, table formats and similar cannot be copied

A great improvement would be the possibility to highlight a paragraph/section/table, etc. in an issue description, click quote, and have only this content quoted in the comment edit field, preversing all formatting (colors, hyperlinks, tables, etc.)