WP FOFT Loader

This plugin implements and automates Zach Leatherman’s “Critical FOFT with preload, with a polyfill fallback emulating font-display: optional” to optimize and speed up web font loading and improve UX by minimizing Flash of Invisible Text, Flash of Unstyled Text, and DOM Reflow. See https://github.com/zachleat/web-font-loading-recipes#the-compromise-critical-foft-with-preload-with-a-polyfill-fallback-emulating-font-display-optional.

Acknowledgement

This plugin is based on Hugh Lashbrooke’s Starter Plugin, a robust and GPL-licensed code template for creating a standards-compliant WordPress plugin.

PRO only features

• Support for 7 additional font-weights
• Small-caps support
• Finer-grained control of default CSS
• Default options reset
• Warn user of unsaved changes when navigating plugin tabs

Configuration

Video Tutorials

Episode 1. Intro and Background

Episode 2. Font Squirrel Generator (WOFF & WOFF2)

Generating and Uploading the Font Files

Upload two files for each web font: a WOFF file and a WOFF2 file. We recommend you use Font Squirrel’s Webfont Generator to generate the files. Mandatory Font Squirrel settings are:

Select “Expert” Font Formats: “WOFF” “WOFF2” Advanced Options: “Font Name Suffix” = -webfont 

For detailed recommended settings, see the plugin Upload options screen.

Filenames must follow the proper naming convention: $family–$variant-webfont.$filetype.

$family

The font family base name without style. Case-insensitive. May contain letters, numerals, and underscores but no hyphens or spaces.

$variant

The font style. Can be weight, style, or a combination of both. Case-sensitive.

-webfont

Mandatory suffix. Append to $variant.

$filetype

The file type, i.e., “woff” or “woff2”.

Example: for the bold weight italic style of Times New Roman, rename the files to timesnewroman-boldItalic-webfont.woff and timesnewroman-boldItalic-webfont.woff2.

Allowed weights and styles and their CSS mappings are:

• regular | normal (maps to 400)

• italic (maps to 400)

• boldItalic (maps to 700)

For small-caps support and extended font-weight support, please upgrade to WP FOFT Loader PRO.

This plugin supports 1 – 4 font families. For example, you might have a display font for headings, a serif-font for body text, a sans-serif font for UI elements, such as navigation labels, and a monospaced font for tabular data and code examples.

Subset

Upload up to 4 small, subsetted fonts. For each font, upload a WOFF & WOFF2 file (for a total of up to 8 files). Each font will act as a placeholder until the full fonts load.

Filenames must follow the proper naming convention: $family-optimized.$filetype.

$family

The font family base name without style. Case-insensitive. May contain letters, numerals, and underscores but no hyphens or spaces. Each $family base name should match the name used for the matching font uploaded on the previous upload screen.

-optimized

Mandatory suffix. Append to $family.

$filetype

The file type, i.e., “woff” or “woff2”.

Example: If you uploaded timesnewroman-regular-webfont.woff and timesnewroman-regular-webfont.woff2 as your body font on the previous screen, name the subsetted versions timesnewroman-optimized.woff and timesnewroman-optimized.woff2 respectively.

To subset and encode your fonts, we recommend you use Font Squirrel’s Webfont Generator. Mandatory Font Squirrel settings are:

Select “Expert” Font Formats: “WOFF” “WOFF2” Fix Missing Glyphs: None Subsetting: “Custom Subsetting” with the Unicode Ranges 0065-0041-005A,0061-007A Leave everything else unchecked OpenType Features: None OpenType Flattening: None CSS: Leave unchecked Advanced Options: “Font Name Suffix” = -optimized 

For detailed recommended settings, see the plugin Subset options screen.

CSS

@import rules are automatically handled by this plugin. You may manually inline your font-related CSS in the document <head> here. Place rules pertaining only to the font-family, font-weight, font-style, and font-variation properties here.

Plugin CSS

The plugin loads some CSS by default. You may disable it from this screen.

Font Display

The plugin uses font-display: swap by default. You can override the font-display property here.

CSS Stage 1

Declarations placed in this field will load subsetted fonts as placeholders while the full fonts load.

• Use only the family name followed by Subset (case-sensitive)
• Family names must match the names you input on the “Subset” screen.
• All declarations must start with the fonts-stage-1 class

See the Documentation screen to view the Stage 1 CSS that this plugin loads by default.

Incorrect:

.nav-primary { // Missing class: .fonts-stage-1 font-family: latoSubset, sans-serif; } .fonts-stage-1 #footer-secondary { font-family: lato, san-serif; // Missing “Subset” suffix } .fonts-stage-1 div.callout { font-family: latoSubset, san-serif; font-size: 1rem; // “font-family,” “font-weight,” “font-style,” // and “font-variant” rules only } .fonts-stage-1 div.callout { font-family: latosubset, san-serif; // “Subset” suffix is case-sensitive } 

Correct:

.fonts-stage-1 .nav-primary { font-family: latoSubset, sans-serif; } 

CSS Stage 2

• Use only the family name
• Family names must match the file names for the fonts you uploaded on the “Upload” screen.
• Omit weights and styles from the font name
• All declarations must start with the fonts-stage-2 class
• For best performance, please minify your CSS before pasting it into the form.

See the Documentation screen to view the Stage 2 CSS that this plugin loads by default.

Incorrect:

tbody { // Missing class: .fonts-stage-2 font-family: lato, Corbel, "Lucida Grande", sans-serif; font-weight: 400; font-style: normal; } .fonts-stage-2 span.bolder { font-family: lato-bold, Corbel, "Lucida Grande", sans-serif; // Don’t include style in font name. // Better yet, omit declaration altogether. font-weight: 700; } .fonts-stage-2 div.callout { font-family: lato-regular, Corbel, "Lucida Grande", san-serif; font-size: 1rem; // “font-family,” “font-weight,” “font-style,” // and “font-variant” rules only } 

Correct:

.fonts-stage-2 div.callout { font-family: lato, Corbel, "Lucida Grande", sans-serif; font-weight: 400; font-style: normal; } .fonts-stage-2 div.callout { // No need to redeclare the font-family — all weights map to a single family name font-weight: 700; // This will use the lato-bold font } 

For best performance, please minify your CSS before pasting it into the form.

Font Stacks

Change the default font fallbacks in case your custom fonts don’t load. Don’t include the names of your default custom fonts here.

Further Documentation

See the Documentation screen to view the CSS this plugin loads by default and to view video tutorials.

Translations

• English: Default language, always included

Would you like to help translate WP FOFT Loader into your own language? You can do that here!

Dependencies

This plugin includes these third-party libraries in its package.

• HTMLPurifier
• CSSTidy
• Fontawesome