Finding the Source of a Conflict With Flash Player

I searched for a question similar to mine and did not find one. My apologies in advance if this has already been discussed.

I am planning to move my websites to Weebly from Homestead.  The Weebly editor currently has elements which use Adobe Flash Player. When I view the Weeby editor in Firefox, some of the screen content doesn't display correct. I was told to enable Adobe Flash in Firefox, which I did. I still cannot see the screen as it is intended and I have been told by Weebly that I must have an ad-on or plugin which is creating a conflict.

I honestly do not know enough about this subject to determine the source of my conflict with Flash Player. I appreciate any input on this.

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