GitLab

The scheduled manual builds are currently producing a manual with broken search links. The file extension is being set to undefined rather than the expected .html.

It turns out that these builds are using sphinx-build 3.1.2 and searchtools.js now expects DOCUMENTATION_OPTIONS.LINK_SUFFIX rather than DOCUMENTATION_OPTIONS.FILE_SUFFIX which is being produced by layout.

Solution: peg sphinx to the required version. Things can break when a later version becomes available and it has not been tested by us.