document new features

static/releases.html

@@ -315,6 +315,8 @@
             <ul>
                 <li>set SCHED_BATCH in the build system and release generation scripts instead of the interactive shell</li>
                 <li>Vanadium: update Chromium base to 81.0.4044.111</li>
+                <li>disable safe volume feature everywhere instead of only the US</li>
+                <li>hardened_malloc: implement slab allocation memory corruption checks for malloc_usable_size</li>
             </ul>
 
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