Added a note about support for uifigure "unlocking" in various releases

Author: Dev-iL

README.md

@@ -392,6 +392,8 @@ mlapptools.textAlign(myGUI.TextArea, 'right');
 
 This method modifies the properties of the UIFigure controller such that opening the UIFigure in a browser (using the webwindow URL) becomes possible. This method has no effect on MATLAB releases before R2017b (where no such restriction exists in the first place).
 
+_NOTE:_ this method works as expected in releases ≤R2018a. In newer releases, the unlocked figure can only be viewed in the built-in web browser using `web(hWW.URL,'-new')`. This way one can view the source code of the webpage (useful to examine the DOM's hierarchy etc.), but not modify it (by editing the nodes manually or issuing console commands).
+
 ##### Examples
 
 Using the demo GUI generated by `./Demo/DOMdemoGUI.m`
@@ -408,7 +410,8 @@ web(hWW.URL,'-browser'); pause(3);
 mlapptools.unlockUIFig(myGUI.UIFigure);
 
 % Attempt to open again:
-web(hWW.URL,'-browser');
+web(hWW.URL,'-browser'); % Works on R2016a-R2018a
+web(hWW.URL,'-new');     % Works on all releases (probably)
 ```
 The 1<sup>st</sup> browser window should be empty, whereas the 2<sup>nd</sup> should correctly show the contents of the UIFigure.