Use present tense

wiki/src/support/known_issues.mdwn

@@ -464,9 +464,8 @@ Note that your Persistent Volume will be safely preserved.
 Persistent folder disappears and persistent feature configurations do not load
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-Sometimes when Tails is started, the <span class="filename">Persistent</span>
-folder will be missing and the configurations for persistent features will not
-be loaded.
+Sometimes, the <span class="filename">Persistent</span> folder is missing and
+the configurations for persistent features do not load.
 
 Most likely this means that the <span class="filename">persistence.conf</span>
 file has disappeared. However, the files in the