JavaScript `TypeError: synthetic_implementors is null` error on some trait pages

[ollie27]

For example on the nightly docs https://doc.rust-lang.org/nightly/std/iter/trait.Iterator.html:

TypeError: synthetic_implementors is null main1.42.0.js:1:34607
    register_implementors https://doc.rust-lang.org/nightly/main1.42.0.js:1
    <anonymous> https://doc.rust-lang.org/nightly/main1.42.0.js:1
    <anonymous> https://doc.rust-lang.org/nightly/main1.42.0.js:7
ReferenceError: addSearchOptions is not defined search-index1.42.0.js:7:1
    <anonymous> https://doc.rust-lang.org/nightly/search-index1.42.0.js:7

Additionally most of the documentation doesn't load (but not every time):

I suspect this was caused by #68192 (cc @GuillaumeGomez).

[GuillaumeGomez]

Very likely. I'll check how to fix it.