Assuming that "gantt tree" is a task table (is it?), can you describe any use 
cases why do you need it? Why do you 
want fonts in a table to look different than fonts, say, in the menu bar?

I can change colors of bars in the gantt graph (on the right). It would be nice 
that
the same colors were used on the "gantt tree" (on the left), for example.

It would be nice to add the ability to change font style (for eg. bold) to 
remark
that task is very important. 

So you actually need matching colors and some indication of the task priority, 
not just ability to use Comic Sans 
font in the whole table?

yes: matching colors between text (on the left) and bars (on the right) will 
help to recognize faster the 
tasks. Then, the ability to use bold text for some tasks will help to recognize 
some important tasks. 

When you say "important", do you mean task priority?

Yes

There is a "priority" field in task properties and there is a "priority" column 
in the task table. For high priority tasks this column shows a red bullet. Will 
it work for you?

Adding some formatting options would be useful so that the Gnatt chart can be 
made more attractive  and more legible.

The proportions of the bar
The outline around the bar
The font, size of font, bold, italic etc
Add notes
Change the scale of a milestone diamond
etc.

Thanks

Ben

For example when managing a multi-stakeholder project, where many tasks repeat 
among stakeholders (for i.e. companies), the change in font and size can help 
identify which is a group of task, and which is a different stakeholder.  I 
know that the task window on the left, allows you to do indentation, but these 
are not very clear on the bars (right) visually speaking. 

An illustration

Company A
  Group task 1
     Task 1
     Task 2
Company B
  Group task 2
    Task 1
    Task 3

The indentation works on the left side, but not on the bar section, so changes 
in fonts, size and colors would help identify what is what. 

Thanks,
Diego

#9: you can change task colors and it works perfectly for the chart. This 
request is about colors and fonts in the table view.

I would like to add that the current font for displaying Gantt Chart isnt very 
much to the liking of many . If we can have an option to change the font and 
its size, it will be great.

#11 this request is about colors and fonts in the tree table view. 

I will create a separate request. Thank you .

Issue 326 has been merged into this issue.

[deleted comment]

Issue 1013 has been merged into this issue.