WT-7109 has fixed a backward compatibility problem when the configuration options are removed in the newer versions that are used in the older version databases. To find out these incompatible problems much earlier than the customer reported, update the compatibility test to cover these scenarios.

@@ -116,10 +116,6 @@ verify_branches()
            echo "$1/wt verifying $2 access method $am..."
            dir="$2/test/format/RUNDIR.$am"
            WIREDTIGER_CONFIG="$EXT" ./wt $(bflag $1) -h "../$dir" verify table:wt

+            echo "$1/wt dump and load $2 access method $am..."
+            WIREDTIGER_CONFIG="$EXT" ./wt $(bflag $1) -h "../$dir" dump table:wt > dump_wt.txt
+            WIREDTIGER_CONFIG="$EXT" ./wt $(bflag $1) -h "../$dir" load -f dump_wt.txt
        done
}

 
With the above patch, It is possible to test part of the configuration options that are incompatible across the newer versions, but not all the options. Enhance the above test if possible to cover all scenarios, if not merge the above change once WT-7109 is merged into 4.4 branch.