The text pane supports a discrete Find bar. Opened via the Edit -> Find menu or a shortcut, this adds a one-row toolbar to the top of the text pane (and beneath any Displayed Attributes). If Find & Replace is required, the bar expands to 2 rows.
Matches to the find string are case-insensitive and regular expressions are not supported.
The results if a find in $Text will highlight all matches in the current text and lists the total count of matches (if any) at the right-hand end of the search string input box. The two chevron button aloo the cursor to be cycled through the matches in the $Text.
Ticking the Replace box toggles additional find & replace controls.
The Done button closes (hides) the Find toolbar. Note that the current find string is remembered during the current session so can easily be re-used.