diff --git a/tools/linuxfs/overlay/usr/local/bin/bannerlator-session b/tools/linuxfs/overlay/usr/local/bin/bannerlator-session
index 318e7a0ed..65e6e414e 100755
--- a/tools/linuxfs/overlay/usr/local/bin/bannerlator-session
+++ b/tools/linuxfs/overlay/usr/local/bin/bannerlator-session
@@ -312,18 +312,35 @@ case $mode in
       # in yet - so the install dialog only appeared after the user restarted the client by hand.
       # With no remembered sign-in, ask again once the sign-in has happened: the client binary
       # started a second time with a URL hands it to the running instance and exits.
+      #
+      # The request is also dropped while the client is still in its post-logon compat phase (it
+      # probes every registered tool then): with publicbeta 1790380355 that phase took 27 s and a
+      # request sent 15 s after sign-in vanished (2026-09-26, no dialog; 1790121765 was done in
+      # time). So wait for the client to say the phase is over ("Waiting for compat in post-logon
+      # took" in its console log; at most 90 s if it never does), then ask - and ask again, twice
+      # at most, if no install has started a minute later.
       if ! grep -q '"RememberPassword"[[:space:]]*"1"' "$steam_root/config/loginusers.vdf" 2>/dev/null; then
         (
+          _bl_acf="$steam_root/steamapps/appmanifest_4427310.acf"
           _bl_conn="$steam_root/logs/connection_log.txt"
+          _bl_cons="$steam_root/logs/console_log.txt"
           _bl_from=$(stat -c %s "$_bl_conn" 2>/dev/null || echo 0)
+          _bl_cfrom=$(stat -c %s "$_bl_cons" 2>/dev/null || echo 0)
           for _ in $(seq 1 180); do
             sleep 10
-            [ -f "$steam_root/steamapps/appmanifest_4427310.acf" ] && exit 0
+            [ -f "$_bl_acf" ] && exit 0
             if tail -c +$((_bl_from + 1)) "$_bl_conn" 2>/dev/null | grep -q "RecvMsgClientLogOnResponse() : processing complete"; then
-              sleep 15
-              [ -f "$steam_root/steamapps/appmanifest_4427310.acf" ] && exit 0
-              step "signed in: asking the client again for the ARM64 Proton"
-              "$steam_root/steamrtarm64/steam" steam://install/4427310 >/dev/null 2>&1 || true
+              for _ in $(seq 1 45); do
+                tail -c +$((_bl_cfrom + 1)) "$_bl_cons" 2>/dev/null | grep -q "Waiting for compat in post-logon took" && break
+                sleep 2
+              done
+              for _bl_try in 1 2 3; do
+                sleep 10
+                [ -f "$_bl_acf" ] && exit 0
+                step "signed in: asking the client again for the ARM64 Proton (try $_bl_try of 3)"
+                "$steam_root/steamrtarm64/steam" steam://install/4427310 >/dev/null 2>&1 || true
+                sleep 50
+              done
               exit 0
             fi
           done