# How to set font size on graphical debugger?
**URL:** https://swi-prolog.discourse.group/t/how-to-set-font-size-on-graphical-debugger/1723
**Category:** Tools
**Created:** [January 8, 2020, 6:28pm UTC](https://swi-prolog.discourse.group/t/how-to-set-font-size-on-graphical-debugger/1723 "2020-01-08T18:28:45Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@peter.ludemann](https://swi-prolog.discourse.group/u/peter.ludemann)
#### Post date: [January 8, 2020, 6:28pm UTC](https://swi-prolog.discourse.group/t/how-to-set-font-size-on-graphical-debugger/1723/1 "2020-01-08T18:28:45Z")
I can I increase the sizes of everything in the graphical debugger? I need a magnifying glass to read it.
Background: I’m trying to debug a server, and the only way seems to be tspy/1, which brings up the graphical debugger. Normally, I use the old&trusty debugger under emacs, or add print statements to my code.
Alternatively: is there a way to run http\_server in non-threaded mode so that spy/1 and friends work? (Yes, I know that this causes other problems when there are multiple requests to the server.)
---
### Author:  [@Boris](https://swi-prolog.discourse.group/u/Boris)
#### Post date: [January 8, 2020, 6:48pm UTC](https://swi-prolog.discourse.group/t/how-to-set-font-size-on-graphical-debugger/1723/2 "2020-01-08T18:48:14Z")
The `font.scale` variable in the “Editor preferences” is also used for the debugger. You can edit it in PceEmacs, just start it:
```prolog
?- emacs.
```
and then go to “Edit” --\> “Editor preferences”.
I don’t know how to “reload” the settings. I had to “halt” and then start the interactive interpreter again for the changes to take effect.
---
### Author:  [@peter.ludemann](https://swi-prolog.discourse.group/u/peter.ludemann)
#### Post date: [January 8, 2020, 7:18pm UTC](https://swi-prolog.discourse.group/t/how-to-set-font-size-on-graphical-debugger/1723/3 "2020-01-08T19:18:16Z")
Yes, editing `~/.config/swi-prolog/xpce/Defaults` `font.scale` did the trick (almost). I had to remove the leading `!` (having forgotten the conventions for X11 config files).
I’ll have to do some more fiddling to get the debugger help displaying at a size I like.
@jan - if the debugger help is available in the SWI-Prolog online documentation, I couldn’t find it and “grep” only found me `xpce/prolog/lib/trace/pltracer.hlp`.
---
### Author:  [@grossdan](https://swi-prolog.discourse.group/u/grossdan)
#### Post date: [September 5, 2025, 7:47am UTC](https://swi-prolog.discourse.group/t/how-to-set-font-size-on-graphical-debugger/1723/4 "2025-09-05T07:47:14Z")
Is there a way to disable this feature completely – just keep the fonts at a constant size