Highlighting a portion of text in, 'Say something with text
do speech' dialog now only previews the selected text instead
of previewing all the text. To preview all text, either
select no text or all of the text.
When "Preview" is clicked, the words spoken are highlighted. When the TTS is finished, nothing remains highlighted, and so another click of the "Preview" button will speak the entire text again.
However, if "Stop" is pressed while a preview is in progress, the last spoken word remains highlighted, and another click of the "Preview" button will only speak that word.
I installed the release version so I could observe the original behaviour, which is to remove the highlight when "Stop" is clicked in the middle of a preview.