Lighthouse report recommendations

[laineyhm]

• The following error was logged to the console: Error while trying to use the following icon from the Manifest: https://staging.languageforge.org/images/lf-logo-144-xxhdpi.png (Download error or resource isn't a valid image) - fixed in PR 1739

• Add a lang attribute to the html element

• Include the right link to the manifest in the index.html file

• Add source maps for large first-party JavaScript
  Added for vendor, main, and manifest
  

• Add a meta description to be displayed in search results

• Add a valid robots.txt file so that crawlers can crawl and index the site

• Cache more static resources

• Update/remove front-end JavaScript libraries with known security risks; for us, this is JQuery

• There is an issue stemming from a Google/YouTube cookie.

Deferring

• Ensure text remains visible during webfont load by putting font-display: swap in the @font-face style. LM: It seems like the file that is being complained about is not editable. (font-awesome-webfont.woff2)
• Add [alt] attributes to images
• Eliminate render-blocking resources
• Try to lower network payloads
• Add names to buttons that screen-readers can read
• Add labels to forms that screen-readers can read
• Make links crawlable. LM: I'm not sure this is worthwhile to do, since a lot of the links inside the editor would probably not be useful to search engines.