@julieqiu Before moving ahead, I want to conform about the responseText messages with clickable links
for https://github.com/golang/pkgsite/blob/master/internal/frontend/fetch.go#L208 the responseText would be

Package github.com/module/pkg-nonexistent could not be found, but you can view module “github.com/module” at <a href="https://pkg.go.dev/mod/github.com/module" target="_blank">https://pkg.go.dev/mod/github.com/module</a>.

and for https://github.com/golang/pkgsite/blob/master/internal/frontend/fetch.go#L190 responseText would be

<a href="https://pkg.go.dev/mod/github.com/valid/module_name/foo@v1.0.0" target="_blank">github.com/valid/module_name/foo@v1.0.0</a> is not a valid path.

shall I go ahead with these responseText messages? some guidelines would be helpful :)

Please do, thanks @vikramcse! Some minor tweaks:

https://github.com/golang/pkgsite/blob/a956e7c37d48f27cd948f10ab6da5cfaff09302c/internal/frontend/fetch.go#L231

github.com/notvalid/module_name/foo@v1.0.0 is not a valid path. Were you looking for "<a href="https://pkg.go.dev/mod/github.com/valid/module_name/foo@v1.0.0" target="_blank">github.com/valid/module_name/foo@v1.0.0</a>"?

https://github.com/golang/pkgsite/blob/a956e7c37d48f27cd948f10ab6da5cfaff09302c/internal/frontend/fetch.go#L250

Package github.com/module/pkg-nonexistent could not be found, but you can view module “github.com/module” at <a href="https://pkg.go.dev/mod/github.com/module" target="_blank">pkg.go.dev/mod/github.com/module</a>.

Hi @julieqiu
I am able to run the frontend server and able to reproduce the above case.

responseText contains text with html containt (anchor tag)

below code snippet from https://github.com/golang/pkgsite/blob/master/internal/frontend/details.go#L502 which renders the errors

epage: &errorPage{
	messageTemplate: template.MakeTrustedTemplate(`
		<h3 class="Error-message">{{.StatusText}}</h3>
		<p class="Error-message">{{.Response}}</p>`),
	MessageData: struct{ StatusText, Response string }{http.StatusText(status), responseText},
}

I tried looking into the documentation of package https://github.com/google/safehtml to convert responseText into HTML
but could not find the proper method.

I also tried template.MustParseAndExecuteToHTML() which will give parsed html, but this method accepts untyped string stringConstant which is unexported.

what could be the proper method the parse above text?

Change https://golang.org/cl/277117 mentions this issue: internal/frontend: Make links on 404 => Request page clickable