diff --git a/libs/web/tracker/presenters/src/lib/pages/issue.page.scss b/libs/web/tracker/presenters/src/lib/pages/issue.page.scss
index 21f44b9..f5db3c3 100644
--- a/libs/web/tracker/presenters/src/lib/pages/issue.page.scss
+++ b/libs/web/tracker/presenters/src/lib/pages/issue.page.scss
@@ -24,6 +24,9 @@
 
 .ts-issue__main {
   display: grid;
+  // Without it the column takes the width of its widest field: on a phone,
+  // wider than the screen.
+  grid-template-columns: minmax(0, 1fr);
   gap: 2rem;
   min-width: 0;
 }