In prior IDEs 1.x I could edit a file called theme.txt and change console.error.color to show errors in yellow which is better for my eyesight than dark red on black. I have spent hours trying to find a clue but, sadly, I am clueless. So, does anyone know how can I do that now? Thanks

Hi @BNNORMAN. I am not aware of any easy way to modify the default themes of Arduino IDE 2.x. You might be interested in these instructions a forum member shared for installing any of the many available 3rd party themes or even creating your own theme: [image] Personal themes IDE 2.x Hi @F6EEQ. Arduino IDE 2.x uses a completely different theme system than Arduino IDE 1.x, so none of the information about the 1.x theme system is applicable in any way to Arduino IDE 2.x. Arduino IDE 2.x is built on the Eclipse Theia IDE framework, which allows it to use VS Code themes. Table of Contents Install a Pre-Made Theme Find Theme Install Theme in Arduino IDE Make a Custom Theme Generate VS Code Extension Template Design Theme Manually VS Code Theme Studio Install Theme in A…

Thanks for the fast response. Ill take a look. It's a real eyestrain for me red on black.

Although it is still red on black, the Arduino IDE developers recently changed the red to a lighter color that has better contrast: Update themes arduino:main ← arduino:themes/themes-update opened 05:05AM - 27 Jan 23 UTC [github-actions[bot]] github-actions[bot] +6 -4 Automated changes by [create-pull-request](https://github.com/peter-evans/create…-pull-request) GitHub action Use a more readable color for "Output" view stderr text in the "Light (Arduino)" theme opened 12:48PM - 21 Jun 22 UTC closed 08:27AM - 15 Feb 23 UTC [per1234] per1234 type: enhancement conclusion: resolved topic: theme topic: accessibility ### Describe the request Use a brighter red/orange color for the stderr text …printed in the "**Output**" view when using the "**Light (Arduino)**" theme. I suggest using the Arduino IDE 1.x coloration as a reference, since this has already been user tested for years with favorable opinions (with the exception of those with color blindness, for whom a specialized theme will be more suitable anyway). It is defined here: https://github.com/arduino/Arduino/blob/43b0818f7fa8073301db1b80ac832b7b7596b828/build/shared/lib/theme/theme.txt#L32 ```text console.error.color = #E34C00 ``` 🙂 The "**Output**" view will be easier and more enjoyable to read. ### Describe the current behavior During the compilation or upload operations, output from the processes may be printed to the "**Output**" view. In order to make it easier to differentiate the types of information conveyed there, output that was written to the standard error stream is colored differently from the output written to the standard output stream (https://github.com/arduino/arduino-ide/pull/1064). The color used for stderr text when the default "**Light (Arduino)**" Arduino IDE theme is active is a fairly dark red color. Some years ago, this coloration in the Arduino IDE 1.x theme was changed from a brighter color to a dark red very similar to the one currently in use by Arduino IDE 2.x's "**Light (Arduino)**" theme (https://github.com/arduino/Arduino/commit/501333a8ef1fbaf5438fe1613003d146bcc697a8). That resulted in complaints from the users: - https://github.com/arduino/Arduino/issues/2901 - https://github.com/arduino/Arduino/issues/3056 Until the change was reverted (https://github.com/arduino/Arduino/commit/8020c0d7339ede208f4a60934e65efb9a52b63df). So I think we already have clear evidence that the current coloration in the Arduino IDE 2.x "**Light (Arduino)**" theme is not ideal. Arduino IDE 2.x: ![image](https://user-images.githubusercontent.com/8572152/174802768-dc91ff1f-4f78-4298-a28c-b6330f1dce99.png) Arduino IDE 1.8.19: ![image](https://user-images.githubusercontent.com/8572152/174802788-4ada5822-d712-4368-b09d-f66362749e4d.png) 🙁 This very important text is difficult and unpleasant to read. ### Arduino IDE version 2.0.0-rc7-snapshot-4611381 ### Operating system Windows ### Operating system version 10 ### Additional context See https://github.com/arduino/arduino-ide/pull/1064#issuecomment-1157293078 for more information on the subject. --- With the exception of "**Light (Theia)**" (which has a white "Output" view background), the other themes use a brighter color. --- Also reported at: - https://forum.arduino.cc/t/which-preference-setting-changes-compilation-message-font-colour/1060578 - https://forum.arduino.cc/t/arduino-ide-2-0-0-rc9-2-available-for-download/1021046/6 ### Issue checklist - [X] I searched for previous requests in [the issue tracker](https://github.com/arduino/arduino-ide/issues?q=) - [X] I verified the feature was still missing when using the latest [nightly build](https://github.com/arduino/arduino-ide#nightly-builds) - [X] My request contains all necessary details That change is already in the nightly build of Arduino IDE, so if you think that might be sufficient for your needs, you can give it a try. The nightly build download links are listed here: https://www.arduino.cc/en/software#nightly-builds The nightly build can coexist with Arduino IDE 2.0.3, so you are welcome to have both installed on your computer at the same time if you aren't sure whether you want to switch from 2.0.3 to the nightly build for good.

Ok, I downloaded the nightly but haven't installed it yet --- here goes. Thanks for that.

Still too dark. There was no installer so I assumed I just replace c:\program files\arduino IDE with the extracted files. In fact I renamed the old Arduino IDE folder and created a new one to copy the files etc into. I guess I'm going to have to read the theia docs.(another day).

I might give up on this since I can copy and paste the error messages but before then... In here there are two theme files C:\Program Files\Arduino IDE\resources\app\node_modules\arduino-ide-extension\src\browser\data dark-color-theme.json default-color-theme.json These contain RGB colour values, one of which is 'errorForeground' sadly, changing the entries to #FFFF00 (yellow) in both files made no difference. ~/.Arduino IDE/settings.json tells me it is using "workbench.colorTheme": "arduino-theme" But I have been unable to find that, assuming it's actually called arduino-theme.json

[image] BNNORMAN: changing the entries to #FFFF00 (yellow) in both files made no difference. I think you would need to build Arduino IDE from source after making that change. The instructions for running Arduino IDE from source code are here: https://github.com/arduino/arduino-ide/blob/main/docs/development.md#development-guide Unfortunately that is a bit advanced and inconvenient, which is why I said "I am not aware of any easy way" in my previous reply. [image] BNNORMAN: ~/.Arduino IDE/settings.json tells me it is using "workbench.colorTheme": "arduino-theme" But I have been unable to find that, assuming it's actually called arduino-theme.json It is the default.color-theme.json file you found. The arduino-theme ID is mapped to that data file here: arduino/arduino-ide/blob/01ee045beb1cd69b23bc68c83b918bb14ab6ef91/arduino-ide-extension/src/browser/theia/core/theming.ts#L6-L7 export const Light: Theme = { id: 'arduino-theme', arduino/arduino-ide/blob/01ee045beb1cd69b23bc68c83b918bb14ab6ef91/arduino-ide-extension/src/browser/theia/monaco/monaco-theming-service.ts#L9-L14 const { Light, Dark } = ArduinoThemes; this.registerParsedTheme({ id: Light.id, label: Light.label, uiTheme: 'vs', json: require('../../../../src/browser/data/default.color-theme.json'),

Thanks for that explanation. I find it odd that, under the bonnet, theme files are present but they are baked in - i.e. no way to change the colour scheme, well, no way that I have found using the advanced preferences, unless I'm missing something. As you said, it's complicated to build my own version - loads of extras to install for a one-shot use. I did find out something new , to me, Windows Subsystem for Linux which I will install. As for getting into modding/building the IDE, I don't think so. Perhaps, if it isn't already on the to do list : User Modifiable Themes could be added (unless it's hidden from me already). Thanks for your insights. I'll get on with the project I was working on before this.

[image] BNNORMAN: if it isn't already on the to do list : User Modifiable Themes could be added Here it is: Add "Generate Color Theme from Current Setting" command opened 11:04AM - 21 Oct 19 UTC [sstaub] sstaub type: enhancement topic: theme ### Describe the solution you'd like Add a "Generate Color Theme from Current… Setting" that generates a theme from the currently selected theme, to use as a starting point for making custom VS Code theme extensions. ### Additional context This feature is available when using [**VS Code**](https://code.visualstudio.com/): #### Additional requests - https://forum.arduino.cc/t/how-to-get-all-my-1-18-19-libraries-installed-in-2-0-1/1050248/3 - https://forum.arduino.cc/t/arduino-ide-v2-hangs-at-start-up/1030052/9 - https://forum.arduino.cc/t/changing-ide-fonts/1028827 - https://forum.arduino.cc/t/personal-themes/1024606 - https://forum.arduino.cc/t/highlighting-of-errors/1018281/3 - https://forum.arduino.cc/t/high-contrast-theia-theme-changed-and-other-issues/1001842/16 - https://forum.arduino.cc/t/how-to-install-vscode-color-theme-extensions/990374 - https://github.com/arduino/arduino-pro-ide/issues/199 However, note that the custom theme instructions I linked previously essentially provide this already. The missing piece would be for Arduino to decide to formally support that usage by publishing documentation (it is a "you're on your own" undocumented feature currently).

In my personal view, there should be a theme file (json, ...) in the .arduino directory that the user can modify to his/her heart's content. No difficult fiddling with installation. I did find some json files somewhere in the past but modifying those did not seem to work.

IDE 2.0.3 How to change compiler error message colour?

Development Tools IDE 2.x

ptillisch February 26, 2023, 3:28pm 2

Hi @BNNORMAN. I am not aware of any easy way to modify the default themes of Arduino IDE 2.x.

You might be interested in these instructions a forum member shared for installing any of the many available 3rd party themes or even creating your own theme:

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IDE 2.0.3 How to change compiler error message colour?

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