1,784,655 bytes to 36,616, by moving one file
A 6664px screenshot displayed at 672px is 99 percent waste.
The desktop screenshot is 6664 × 2168 and 1.74 MB. It was being served at full size into a column about 672px wide. Every byte past that width was downloaded and thrown away.
What surprised me is that the fix isn’t a setting. It’s where the file lives.
From this:
content/posts/first-try.md
assets/my-virtual-desktop-setup.png
to this:
content/posts/first-try/index.md
content/posts/first-try/my-virtual-desktop-setup.png
That’s a page bundle, and inside one the image stops being a loose asset
and becomes a page resource — reachable via .Page.Resources.Get, carrying
its own front matter for alt text and caption and credit, and eligible for
.Resize. The theme’s figure partial then does what it already does for its
own images: anything over 1400px wide gets resized and converted to WebP at
q82.
1,784,655 bytes → 36,616 bytes
Forty-eight times smaller. I compared them at display size and can’t tell them apart.
The rule underneath, which I think is the actual lesson of the last hour: a
file’s location determines what Hugo is permitted to do with it. static/
is frozen. assets/ is processable. A page bundle is processable and carries
metadata. Put images in bundles.