I usually don't highlight text to quote, but it worked for me.

I tried replicating this issue. Looks like the quote button does not pop up if you have the "white space" under the last line selected:

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But (carefully) making sure that you select up until the dot does seem to work:

pasted_image (resized).png

Not sure if that's what's happening?

I just tried this, and, you're right, it didn't work. Learned something new today. I usually just click on the quote button in the bottom right corner.

Yup, triple click indeed doesn't work. I'll see if I can fix that.

If you want to quote the whole post just use the quote marks next to the link icon at the bottom right. If you want to just quote part, then click, hold and drag the part you want to quote and click the blue quote text that appears when you unclick.

Regardless I wouldn't do the triple click, I'd just click on the quote mark at the lower right to quote everything.

I've noticed this same behavior and found this thread. It's not just triple-click. If you drag vertically to select the last line(s) of a post you get the same behavior with the addition of it highlighting blue vertical bars (blanks) on either side of the quote icon. It's almost like it is trying to highlight an unprintable character at the end of the post since it works correctly as long as you carefully select only through the last visible character.

This happens in both Microsoft Edge and Google Chrome for me.

Not a big deal at all, especially now that I see the work-around. Pinside already works better than 99.9% of the web sites out there, so thanks for all you do.