Linter findings

Every finding here is something the console does silently. Your widget renders, part of it does not work, and nothing anywhere says why. The linter reports them in the harness's inspector, on every HTTP API response, and to the test driver, where an assertion on an empty finding list turns each one into a failing test.

Stripped by the sanitizer

• A script, iframe or use element.
• An event-handler attribute such as onclick.

These are removed before rendering. See rendering rules.

Broken cwdb-action

• A cwdb-action with no element before it. It binds to nothing.
• action="call" with no endpoint. There is nothing to invoke.
• event="mouseenter" on a call. mouseenter works only with html.
• Content that is not valid JSON on a call.

See cwdb-action.

Fields that never arrive

• A form field without a name. It is never collected into forms.all, so the handler reading it gets nothing and cannot tell that from an empty value.

A widget that did not render

• The answer is the error page the runtime writes when a handler threw. It is HTML and it renders, so nothing else about the response says the invocation failed.
• The answer is a JSON object rather than HTML or markdown. The console displays it as text.

Both are what Assert.Empty(page.Findings) is for: a throttled query and a successful one arrive as the same shape, and without these the headline assertion passes on a widget that showed a viewer nothing. ShownWidget.Failed says the same thing directly.

CSS that reaches other widgets

• A stylesheet rule whose selector does not lead with a class or an id of your own — td { }, svg { }, table.rows td { }. Every widget on a dashboard shares one page, so these can match whatever the widgets beside yours rendered.

This is the one advisory rule here. Everything above is a defect; this one depends on a question nobody has answered. AWS's own samples write bare td { } freely, which only works if the console scopes each widget's stylesheet to that widget, and nothing AWS publishes says it does.

The rule assumes it does not, because the two ways of being wrong are not symmetric. If the console does isolate and we warn anyway, you ignore a finding. If it does not and we stay quiet, you ship a widget that restyles a colleague's on a shared dashboard and hear about it from the colleague.

.rows td { } is correct either way, so the fix costs nothing. See status for the probe that settles it.