It's a draft, not an error. It's on L10n-bot's review list (and should be able to view) because he's on the list of reviewers.

We should really make the error nicer when viewing a draft (tweaking summary to that).

(In reply to comment #1)

It's a draft, not an error.

We should really make the error nicer when viewing a draft (tweaking summary
to
that).

Since it's a draft that I am not allowed to view, shouldn't that change be
hidden from the dashboard (if I look at L10n-bot's dashboard)?

It looks like a gerrit search problem (dashboard is just three searches).
Because if I search for

message:"improved version"

the change shows up as well.
/me shudders as I'll have to touch gerrit's search implementation again :-(

I had a quick look at the visibility checks when searching for
drafts, and they basically look sane.

When running the query

message:"improved version"

the returned JSON for the above change gets reported with

"status":"NEW"

instead of

"status":"DRAFT"

. Are we sure it's a draft?

When mirroring the repo locally, I noticed that although

changes/58/58858/6
...
changes/58/58858/13

are present, the refs

changes/58/58858/1
...
changes/58/58858/5

are missing.

This repo comes with more such omissions. Some of the omissions
belong to valid, visible changes e.g.:

https://gerrit.wikimedia.org/r/#/c/52776
^ misses patch sets 1-9

Others don't show (and do not show up when searching for them)

https://gerrit.wikimedia.org/r/#/c/55287
^ misses patch sets 1-9

Do we know if something happened to that repo sometime back?