DVT VHDL IDE User Guide
Rev. 20.1.5, 27 March 2020
You can increase/decrease the font size in code editors using these buttons, on the main toolbar:
You can can also modify the font settings from Window > Preference > General > Appearance > Colors and Fonts. For global settings (used by all editors), select Basic > Text Font and for editor specific settings, select (e , Verilog, VHDL) Language > Editor > Text Font.