You can make unselectable text on a webpage selectable by going into the browser inspector and disabling any "user-select" or similar CSS property. You can also inject a "user-select: all" into the HTML element containing the text if you can't find which parent element has the "user-select: none".

You can also disable any right click blocking JavaScript or other user-hostile JavaScript in the browser inspector by running JavaScript code in the console to remove any HTML event listeners for right click (typically its oncontextmenu so just set "document.body.oncontextmenu" or "{element that has the property set}.oncontextmenu" to something like null or return true).

*The specific procedure will be slightly different for every site because it is written differently.