This issue solely affects `hkrailwiki` ([[https://hkrail.miraheze.org/|hkrail.miraheze.org]]).
**Steps to reproduce bug**
* Head to [[https://hkrail.miraheze.org/wiki/Project:沙盒|the sandbox page]] or just any page on `hkrailwiki`.
* Type specifically (a) `[[#雙島式月台]]`, (b) `[[#雙島式月台|any random text]]`, (c) `[[#雙島式月台|雙島式月台]]`, (d) `[[#雙島式月台|三軌雙島式月台]]` **in separate attempts** (do not submit them together) and try to preview or submit.
**Expected result**
All four section pipelinks are rendered as expected.
**Observed result**
Ever since the late December recovery of the wiki from the original database, (a) and (b) functions as expected (control tests), (c) renders as an empty HTML link (anchor `<a>` tag), and (d) results in an MWException, disallowing viewing, saving or previewing of any content with that exact section pipelink.
On saving or previewing (d), the browser sometimes logs an HTTP 500 error, showing that it's likely to be an internal error.
**Additional information**
Per conversation with @Agent_Isai on Discord, this could be a server-side cache problem. This might explain why the import after resetting hkrailwiki had unexpected behaviour, with correct page history but mismatched source code that doesn't even exist in the import but from the deleted November wiki, as discussed in T10173 and in DMs with @Universal_Omega.