SingleFile CLI 2.18.4

CLI fixes and improvements

Update single-file-core to 1.6.32: "Remove unused fonts" (on by default) no longer drops the icon glyphs of fonts that set them through a custom property, such as Font Awesome 7, so the icons are no longer rendered with the fallback font; the displayed srcset candidate keeps its descriptor when the alternative images are removed, so the image is drawn at its original size; JPEG XL images are named .jxl in self-extracting ZIP archives and extracted as image/jxl.
--http-proxy-server now also applies to the requests made outside the browser, the fallback used when the browser could not fetch a resource. These requests used to leave the machine directly, around the proxy. On Deno they go through the proxy with the configured credentials; on Node.js, which has no per-request proxy, they are refused instead.
--browser-executable-path pointing to a Firefox executable without --browser-engine firefox now fails with a message asking for the engine, instead of "Not Found".
An oversized page that cannot be written as one HTML string now fails with a message pointing to --compress-content, --remove-alternative-images, --max-resource-size and --block-images, instead of "RangeError: Invalid string length".

Co-authored by Claude (Claude Code)