Tie to an empty bar

A tie connects notes of the same pitch to result in a single sounding note of the total duration spanned by the tie; Having a tie into a rest therefor doesn't make sense (to me).

You can however use a slur (S) for which the endpoint can be a rest.

[EDIT]Looking up that score it seems it might indicate a "let-ring". Haven't tested this yet, but I assume you can create the normal tied chord and then make the 2nd chord in the new measure invisible: Select it and press V

It is a laissez vibrer (italian: lasciar vibrare, abbrev. l.v.) indication.
I would do this by selecting a note, and then adding in a slur (not a tie, default key: S). This allows me to create fake open ties and I can then readjust it's position. Alternatively, you can open up the master palette's menu for symbols (default key: Z) and then search for 'laissez vibrer'. There will be two options, select the one that fits the stem direction. It will appear inside the notehead, so you'd have to undergo some trouble to move its position.
Another way is to insert a textbox, and then search for the open tie symbol. In the special character's menu (accessed by clicking on the bottom-most left button (it is an 'a' in a box) when editing a textbox), under 'Musical Symbols' -> 'Articulation' there are two little open ties with both directions. Use the one most appropriate, and you can then adjust the size (but not as flexible as a fake slur) by changing the font size as you would with normal text.
For convenience, move this open tie text into your palette by holding down Ctrl+Shift and dragging the element into any palette (make sure that the palette's 'Enable Editing' is checked).

(See https://musescore.org/en/handbook/master-palette, for information on master palettes; https://musescore.org/en/handbook/text-editing, to access special characters; https://musescore.org/en/handbook/palette, for palette editing)