ui/ux improvement

src/components/ErrorBoundary.tsx

@@ -85,8 +85,19 @@ export class ErrorBoundary extends Component<Props, State> {
           {isStale ? 'This page was updated while you were working' : `Something on ${area} failed to render`}
         </h2>
         <p style={{ margin: '0 0 16px', fontSize: 14, lineHeight: 1.6, color: '#5C4747' }}>
+          {/*
+            In DEVELOPMENT nothing was deployed, and saying so sends a developer
+            looking for a release that never happened. The same failure has a
+            different cause here: the dev server restarted, or Vite re-optimised
+            its dependencies after a config change, and either invalidates the
+            module URLs this tab is holding. Same fix, different sentence —
+            `import.meta.env.DEV` is compiled out of the production bundle, so
+            this costs a deployed console nothing.
+          */}
           {isStale
-            ? 'A new version of the console was deployed, so the file this tab was about to load no longer exists. Nothing is wrong with your data — reloading picks up the current version.'
+            ? import.meta.env.DEV
+              ? 'The dev server restarted or re-optimised its dependencies, so the module URL this tab was holding no longer resolves. Nothing is wrong with your code — reloading picks up the current module graph.'
+              : 'A new version of the console was deployed, so the file this tab was about to load no longer exists. Nothing is wrong with your data — reloading picks up the current version.'
             : 'The rest of the console is fine — this is one screen, not the whole app. The message below is what broke, and the full stack is in the browser console.'}
         </p>
         <pre
@@ -109,7 +120,10 @@ export class ErrorBoundary extends Component<Props, State> {
           onClick={isStale ? this.reload : this.reset}
           style={{
             padding: '9px 18px',
-            borderRadius: 999,
+            /* The same corner as every other control on the console. A stadium
+               here made the one button a person sees on a broken screen the one
+               button shaped unlike the rest of the product. */
+            borderRadius: 'var(--card-radius-sm, 10px)',
             border: '1px solid #D9C0C0',
             background: '#FFFFFF',
             fontSize: 14,