Revert "remove unnecessary border-radius already set on the iframe" (#3613)

* Revert "v5.1.18 banner artwork"

This reverts commit 70500140b9.

* Revert "Revert #3607 and #3608"

This reverts commit 87b3e470c2.

* Revert "Fix default global keyboard shortcuts for Mac"

This reverts commit e466f62e7e.

* Revert "Comment plugin: Improve styles"

This reverts commit e17456e3bc.

* Revert "Style tweaks for framed editor + preview (#3608)"

This reverts commit c058378da0.

* Revert "Change to natural counting in range[N] operator (#3609)"

This reverts commit b9df224f99.

* Revert "Update release note contributors list"

This reverts commit 0f3912ba95.

* Revert "Make editor-preview not hide text-editor shadow (#3607)"

This reverts commit 11f02dc362.

* Revert "Editor needs to stand out a bit more (#3606)"

This reverts commit d711ef25ed.

* Revert "Tweak for keyboard-shortcuts how-to (#3605)"

This reverts commit 419ea9a243.

* Revert "Remove unnecessary border-radius already set on the iframe (#3604)"

This reverts commit 288d25e733.

core/modules/editor/engines/framed.js

@@ -96,6 +96,7 @@ FramedEngine.prototype.copyStyles = function() {
 	this.domNode.style.margin = "0";
 	this.domNode.style.resize = "none";
 	this.domNode.style.border = "none";
+	this.domNode.style["border-radius"] = "2px";
 	this.domNode.style["padding-left"] = "0.5em";
 	this.domNode.style["padding-top"] = "0.3em";
 	this.domNode.style["background-color"] = this.widget.wiki.extractTiddlerDataItem(this.widget.wiki.getTiddlerText("$:/palette"),"background");