# Startup error message repository

**URL:** https://discourse.elm-lang.org/t/startup-error-message-repository/1803
**Category:** Request Feedback
**Created:** [August 29, 2018, 9:18pm UTC](https://discourse.elm-lang.org/t/startup-error-message-repository/1803 "2018-08-29T21:18:33Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![MarkDBlackwell](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.elm-lang.org/markdblackwell/32/1225_2.png) [@MarkDBlackwell](https://discourse.elm-lang.org/u/MarkDBlackwell)
#### Post date: [August 29, 2018, 9:18pm UTC](https://discourse.elm-lang.org/t/startup-error-message-repository/1803/1 "2018-08-29T21:18:33Z")

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Where is the system code which generates the message, “Something went wrong when starting your Elm program.”? I haven’t found the relevant repositories.

I’d like to make a PR which would harden the styling of this message, to help beginning Elm programmers who use unusual CSS files.

For example, my use of the rule, `body { font-size: 0 }` caused the error message to be invisible.

So, which repositories are relevant?

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### Author: ![MarkDBlackwell](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.elm-lang.org/markdblackwell/32/1225_2.png) [@MarkDBlackwell](https://discourse.elm-lang.org/u/MarkDBlackwell)
#### Post date: [August 30, 2018, 1:26pm UTC](https://discourse.elm-lang.org/t/startup-error-message-repository/1803/2 "2018-08-30T13:26:26Z")

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I found the relevant repository.

In the compiler’s generated JavaScript output, the function containing that message is:

```
function checkYesFlags(flagDecoder, moduleName)

```

Looking in `elm-stuff/exact-dependencies.json`, I found the function in:

```
"elm-lang/virtual-dom": "2.0.4"
```

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### Author: ![MarkDBlackwell](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.elm-lang.org/markdblackwell/32/1225_2.png) [@MarkDBlackwell](https://discourse.elm-lang.org/u/MarkDBlackwell)
#### Post date: [September 1, 2018, 3:05am UTC](https://discourse.elm-lang.org/t/startup-error-message-repository/1803/3 "2018-09-01T03:05:58Z")

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Elm 0.19 handles this error condition much better, by leaving its target HTML node untouched. Thus, it doesn’t generate any error message in HTML at all. (It logs an error message to the JavaScript console.)

With Elm 0.19, I can keep an appropriate error message in the program’s target node (such as, “You must reset your cache”). And this error message normally disappears, when it’s replaced by the Elm program.

In my original post, I was using Elm 0.18 which, for me, didn’t totally replace its target node, but instead allowed my error message to remain (even in normal operation).

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### Author: ![system](https://canada1.discourse-cdn.com/flex035/uploads/elm_lang/original/1X/50a05e53677a2c3b47776d7abd0f113eb50193a1.png) [@system](https://discourse.elm-lang.org/u/system)
#### Post date: [September 11, 2018, 3:06am UTC](https://discourse.elm-lang.org/t/startup-error-message-repository/1803/4 "2018-09-11T03:06:10Z")

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