[x]):...
There is maybe a css error. Icons represented for editing and deleting could not show properly in file page .

Strange... this is what I see (as I expect):

Things that come to my mind:

You can leave your own comment and find that.
Oh, now I see it! It's a template problem indeed. .code-view is overriding octicons font settings when the comment is inside a code review; perhaps only code should be wrapped in .code-view, while headers and such should be out of it.
templates/repo/issue/view_content/comments.tmpl wraps with view-code
templates/repo/diff/section_unified.tmpl uses octicons, but font gets overriden.
I'll leave that info here in case someone wants to pick up the issue.
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Oh, now I see it! It's a template problem indeed.
.code-viewis overriding octicons font settings when the comment is inside a code review; perhaps only code should be wrapped in.code-view, while headers and such should be out of it.templates/repo/issue/view_content/comments.tmplwraps withview-codetemplates/repo/diff/section_unified.tmpluses octicons, but font gets overriden.I'll leave that info here in case someone wants to pick up the issue.