Offline Page Cache uses user interaction triggers for saving pages.

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 06a962e5f5d7ccf149c6cb7d33398df4a5972375..f91a5e2b9957eed2c9b76e68ba438ed34a7077b7 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -93587,6 +93587,8 @@ value.
   <int value="-1767470652" label="out-of-process-pdf"/>
   <int value="-1751928267" label="disable-icon-ntp"/>
   <int value="-1746767834" label="ssl-interstitial-v2-gray"/>
+  <int value="-1745093325"
+      label="OfflineRecentPagesNavigationTriggers:disabled"/>
   <int value="-1740519217" label="disable-software-rasterizer"/>
   <int value="-1735643253" label="enable-display-list-2d-canvas"/>
   <int value="-1732561795" label="ConsistentOmniboxGeolocation:enabled"/>
@@ -93807,6 +93809,7 @@ value.
   <int value="-813474479" label="site-per-process"/>
   <int value="-812461825" label="AutofillCreditCardSigninPromo:enabled"/>
   <int value="-802348444" label="disable-site-engagement-service"/>
+  <int value="-801077573" label="OfflineRecentPagesNavigationTriggers:enabled"/>
   <int value="-798187384" label="try-supported-channel-layouts"/>
   <int value="-795600188" label="disable-async-dns"/>
   <int value="-780798969" label="disable-single-click-autofill"/>