Not sure if this is a bug or a feature. I currently observe that I often can't start a preview of an environment via context menu. The reason for this is that it only works when the cursor is moved to the opening or closing part of the environment (i.e. somewhere in \begin{xyz} or \end{xyz}) and then use Preview from the context menu (i.e. without having selected the whole code including the environment). By the way a nice feature. But I often forget the condition for this procedure: First move the cursor there. It is not sufficient that the pointer is there. Maybe I'm used to the fact that right click moves the cursor mark to the location (or at least to the line) of the pointer (see notepad++ as an example).

Win10, txs 4.4.1, Qt6, MikTeX