Frame arround forumula in math

Hello!
When I imput a forumula I get grey frame arround.
Please, how can I get rid of it?
Is there a trick?
Many thnaks!

What do you mean “imput a forumula”? the grey frame won’t be in print preview or exported pdf, only can be see at edit mode.

Hello!
I write a doc in .odt and there it is.
U menan if I put it to .pdf it woud disaperar?

It is just a little bit annoying…

Thanks!

yes it would disappear

You can’t explicitly remove the frame or turn off the thin grey outline, but as @leo-wang suggests this thin grey line will not print, but is simply a visual indicator. All formulas are inserted as frame objects. In /content.xml in the ODT an example of the main frame XML is:

<draw:frame draw:style-name="fr1" draw:name="Object1" text:anchor-type="as-char" svg:y="-10.69pt" svg:width="12.56pt" svg:height="13.24pt" draw:z-index="0">
    <draw:object xlink:href="./Object 1" xlink:type="simple" xlink:show="embed" xlink:actuate="onLoad"/>
    <draw:image xlink:href="./ObjectReplacements/Object 1" xlink:type="simple" xlink:show="embed" xlink:actuate="onLoad"/>
</draw:frame>

The object xlink points to /Object 1/content.xml in this example ODT and this is what holds the MathML of the formula.