TYPO3 Core

I have this Flexform-Config

<icon>
                    <TCEforms>
                      <label>Icon</label>
                      <config>
                        <type>group</type>
                        <internal_type>db</internal_type>
                        <appearance>
                          <elementBrowserType>file</elementBrowserType>
                          <elementBrowserAllowed>png,svg</elementBrowserAllowed>
                        </appearance>
                        <allowed>sys_file</allowed>
                        <fieldControl>
                          <elementBrowser>
                            <disabled>false</disabled>
                          </elementBrowser>
                        </fieldControl>
                        <size>1</size>
                        <maxitems>1</maxitems>
                        <show_thumbs>1</show_thumbs>
                      </config>
                    </TCEforms>
                  </icon>

The Browse-Dialog on the right (next to remove) works correct.

But when clicking on the Button called "File" a strange popup is opened, that has no usefull function.

The button should work as the right one.
Also make it possible to hide this button via FielControl->ElementBrowser->Disabled=False. When adding this, both buttons disappear and cannot select files anymore.

Thanks and best regards