The tab preview feature in Microsoft Edge displays a thumbnail glance of an open tab on mouse-over. The thumbnail preview can obstruct features like the bookmarks bar, the address bar, and the forward, back and refresh buttons.There is no standard setting exists to disable tab preview from Microsoft Edge Browser, we can make those settings affected tweaking the windows registry.
To access the Windows 10 registry, type Regedit into the Cortana search box, and click Regedit Run command under Best match.
In Registry Editor, click Edit in the file menu, and select Find.
In the Find what field, input TabbedBrowsing as one word, then click the Find Next button.
Right-click on TabbedBrowsing, click New, then choose DWORD (32-bit) Value.
Change the DWORD value called as NewValue value from #1 to #0 and rename it as TabPeekEnabled. Select base value as “Hexadecimal”
Close the registry window and open Microsoft Edge Browser , now tab previews will no longer be displayed.