LibWeb: Support `line-height: calc(...)` values that resolve to number

This is used on GitHub and many other websites.

1 files changed, 9 insertions, 0 deletions

diff --git a/Userland/Libraries/LibWeb/CSS/StyleProperties.cpp b/Userland/Libraries/LibWeb/CSS/StyleProperties.cpp
index 3c638dac48..403700d462 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleProperties.cpp
+++ b/Userland/Libraries/LibWeb/CSS/StyleProperties.cpp
@@ -219,6 +219,15 @@ CSSPixels StyleProperties::line_height(Layout::Node const& layout_node) const
     }
 
     if (line_height->is_calculated()) {
+        if (line_height->as_calculated().resolves_to_number()) {
+            auto resolved = line_height->as_calculated().resolve_number();
+            if (!resolved.has_value()) {
+                dbgln("FIXME: Failed to resolve calc() line-height (number): {}", line_height->as_calculated().to_string().release_value_but_fixme_should_propagate_errors());
+                return layout_node.font().pixel_metrics().line_spacing();
+            }
+            return Length(resolved.value(), Length::Type::Em).to_px(layout_node);
+        }
+
         auto resolved = line_height->as_calculated().resolve_length(layout_node);
         if (!resolved.has_value()) {
             dbgln("FIXME: Failed to resolve calc() line-height: {}", line_height->as_calculated().to_string().release_value_but_fixme_should_propagate_errors());