diff --git a/lib/container.js b/lib/container.js
index 89e80f3d8..193a42e09 100644
--- a/lib/container.js
+++ b/lib/container.js
@@ -892,6 +892,16 @@ async function loadSupportObject(modulePath, supportObjectName) {
           for (const [key, value] of mapping.entries()) {
             container.tsFileMapping.set(key, value)
           }
+          // Step.line() maps temp paths back through store, not through the
+          // container, so an include has to land there too. Without this a step
+          // that originates in an included .ts page object is printed with the
+          // deleted .temp.mjs sibling. (#5675)
+          if (!store.tsFileMapping) {
+            store.tsFileMapping = new Map()
+          }
+          for (const [key, value] of mapping.entries()) {
+            store.tsFileMapping.set(key, value)
+          }
         } catch (tsError) {
           throw new Error(`Failed to load TypeScript file ${importPath}: ${tsError.message}. Make sure 'typescript' package is installed.`)
         }