Hi verysame, there was a regression bug in chamfering in v4 which is fixed in the current v5 beta which can now chamfer this ok, here it is in the v5 beta:



In v4 fillet is not affected by the regression, you should be able to fillet those edges:





Also in v4 if you include these other edges it should also be able to chamfer ok with a corner juncture patch being made:





- Michael