Mark compatible with Firefox 61.0a1 and SeaMonkey 2.58a1

Note: required hacks https://forum.mozilla-russia.org/viewtopic.php?id=70326 or Nightly
+ extensions.legacy.enabled = true

install.rdf

@@ -20,15 +20,15 @@
 			<Description>
 				<em:id>{ec8030f7-c20a-464f-9b0e-13a3a9e97384}</em:id>
 				<em:minVersion>20.0</em:minVersion>
-				<em:maxVersion>55.0a1</em:maxVersion>
+				<em:maxVersion>61.0a1</em:maxVersion>
 			</Description>
 		</em:targetApplication>
 
 		<em:targetApplication> <!-- SeaMonkey -->
 			<Description>
 				<em:id>{92650c4d-4b8e-4d2a-b7eb-24ecf4f6b63a}</em:id>
 				<em:minVersion>2.17</em:minVersion>
-				<em:maxVersion>2.52a1</em:maxVersion>
+				<em:maxVersion>2.58a1</em:maxVersion>
 			</Description>
 		</em:targetApplication>