Description:
In Writer it is possible to right-click on a tab stop in the ruler to change the type of tab stop. While editing text in a text box, right-clicking on a tab stop in the ruler does nothing. There is no other way to modify tab stop behavior in Draw, either.

Steps to Reproduce:
1.Create a text box and type some text
2.Click on the ruler at the top to create a tab stop
3.Right-click on the tab stop.

Actual Results:  
No context menu appears

Expected Results:
Context menu which displays Left | Right | Center | Decimal


Reproducible: Always


User Profile Reset: No



Additional Info:
Bug initially observed on the latest stable available in Linux Mint 18.3 repository which is 5.1.x. Bug is also observable on 6.0.2.1.

Version: 6.0.2.1
Build ID: 1:6.0.2~rc1-0ubuntu0.16.04.1~lo1
CPU threads: 6; OS: Linux 4.13; UI render: default; VCL: gtk3; 
Locale: en-US (en_US.UTF-8); Calc: group


User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:58.0) Gecko/20100101 Firefox/58.0