Update masthead.html

[dmitrypv]

fix image path in masthead for relative url

This is a bug fix.

Summary

Absolute/relative path check {% if site.logo contains "://" %} for logo image must prepend the baseurl in case of relative path.

Context

If you specify 'logo: "/assets/images/logoexample.png' in _config.yml, logoexample.png will not be shown in masthead unless absolute path is used.

[Geekdude]

This change breaks the site-logo for jekyll 4.0 with a baseurl.

With this change I get ERROR '/~ayoung48/~ayoung48/assets/images/logo88x88.png' not found. If I undo this change, so that the line is {% capture logo_path %}{{ site.logo }}{% endcapture %} this issue goes away.

[iBug]

@Geekdude Hi, can you please share the exact value for your site.logo and site.baseurl? I guess you've manually prepended your base URL to the logo URL, which shouldn't have been done in the first place. I would suggest that you adopt your settings because IMO this PR is the correct way to do it.

[Geekdude]

@iBug Hi, here are the logo and baseurl settings from _config.yml.

baseurl : "/~ayoung48"
logo : "/assets/images/logo88x88.png"

The issue could be related to changes made in jekyll 4.0.
From the update notes:

The link and post_url tags no longer need site.baseurl prepended every time they’re used. Those tags now use our relative_url filter to take care of this for you. Existing uses of the prepending pattern will break though! Sorry! 😅

[mmistakes]

@Geekdude Don't think it's a Jekyll 4.0 issue. That quote above is in reference to when you use Jekyll's {% link %} and {% post_url %} tags to link to pages... we're not doing that with the logo in the masthead.

I think you may be misusing site.baseurl. Could be the ~ to. Can't say that I've seen that in a path before. Can you confirm what a full path to a page on your site should be?

For example. If I had a domain of https://foo.com and wanted all my Jekyll posts/pages to live in a /blog subfolder I'd set the following in my _config.yml

url: "https://foo.com"
baseurl: "/blog"

Which would give me URLs like https://foo.com/blog/my-awesome-post/

With your settings you'd get https://whateveryourdomainis.com/~ayoung48/my-awesome-post/ which looks incorrect to me.

[Geekdude]

@mmistakes I host my website on my university's servers. They use ~username for the student pages. My website is hosted at https://web.eecs.utk.edu/~ayoung48/.

[mmistakes]

@Geekdude OK. That makes more sense then.

[iBug]

@Geekdude Thank you very much for your report. I've reproduced the issue locally and can confirm changes in this PR caused your issue. I've fired up #2385 and hopefully it'll fix this.

[Geekdude]

@iBug Cool, thank you for finding and fixing the issue.