Couldn't find another bug report for this, although this is an extremely noticeable bug so there should be an existing report.
The wiki sandbox for non-admin users is useless because it doesn't show save/preview buttons.
Index: wiki_edit_actions.tpl =================================================================== --- wiki_edit_actions.tpl (revision 18909) +++ wiki_edit_actions.tpl (working copy) @@ -1,3 +1,6 @@ +{if $page eq 'sandbox'} +<input type="submit" class="wikiaction" onmouseover="return overlib('{tr}Preview your changes.{/tr}');" onmouseout="nd();" name="preview" value="{tr}Preview{/tr}" onclick="needToConfirm=false;" /> +{/if} {if $page|lower neq 'sandbox' or $tiki_p_admin eq 'y'} <input type="submit" class="wikiaction" onmouseover="return overlib('{tr}Preview your changes.{/tr}');" onmouseout="nd();" name="preview" value="{tr}Preview{/tr}" onclick="needToConfirm=false;" /> {if $translation_mode eq 'y'}
The above patch add a preview button for the sandbox page always without messing with the save buttons, etc...
To help developers solve the bug, we kindly request that you demonstrate your bug on a show2.tiki.org instance. To start, simply select a version and click on "Create show2.tiki.org instance". Once the instance is ready (in a minute or two), as indicated in the status window below, you can then access that instance, login (the initial admin username/password is "admin") and configure the Tiki to demonstrate your bug. Priority will be given to bugs that have been demonstrated on show2.tiki.org.