Why the "Device Frame" Disappears
In Wondershare Mockitt, a mobile phone frame is built for the mobile project shown in Figure 1. If the size of your project page is exactly the size of the corresponding device meanwhile the "device frame" under preview is selected, a mobile phone frame can appear on the periphery of the page.
If you change the size of a page in the process of editing a project, there is no corresponding device frame for this page anymore, so when you jump to this page, the phone frame will disappear.
For example, by choosing iPhone X as your screen size at the beginning of project creation, you create a total of 10 pages in the editing process.
Among which first 9 pages are the same size based on the iPhone X while the width of the 10th page has been changed for some purpose; then when you run the preview, all the pages except page 10 will display with mobile phone frame under the active “device frame” display. To restore the mobile frame on page 10, just exit the preview, return to the page editing area, and modify the page size of page 10 to iPhone X . (As shown in Figure 2)