Since a few days, I cannot use Discourse inline Quote button when I select text spanning over several paragraphs or going through italic, bold, user mention, code, etc.
I also tried with the default skin/theme, same bug.
I use Firefox 78.5.0esr (64 bits) on Debian 10.
I have just tested same issue with Vivaldi 3.4.2066.106 (Stable channel) (64 bits) on Windows 10.
They are the latest versions of both browsers.
The Quote button does appear when I select a few words of plain text only, now.
Have we change anything recently on our Discourse?
I cannot reproduce this bug at meta.discourse.org but they have a more recent beta version.
It happened on other Discourse forums as well and, as they cannot reproduce on meta, they put the blame on non-standard plugins.
Please try with your browser if the Quote button appears when you try to quote my post by selecting from “I cannot reproduce this bug at” to “a more recent beta version. It happened”: