This applies on mobile (tested latest iOS Safari)
When performing a long search (i.e. one that extends beyond the right margin) there becomes issues editing the search in the future.
e.g. If I search "what dog breeds would be most interested in visiting my Korean BBQ party" and then I later touch the search bar, it becomes hard to get to the end of the search query if I wanted to change it to "what dog breeds would be most interested in visiting my burger cookout"
Making this even more frusturating, using the spacebar to move the cursor to the right, it simply stops near the right margin, it doesn't scroll the text to the right. The only way to scroll is to hold your finger near the right margin to try to move the cursor over, but of course this is also close to the 'X' to clear your search, making it easy to accidentally clear the search.
There are a few options for dealing with this:
- Expand the search bar when clicked on, so it's easier to navigate the mobile cursor with the spacebar or by simply clicking where you want to edit
- Default the cursor to the end of the query, this is the part of the query users most often want to change.
- Allow tapping and "dragging" the text to the left/right to move where you are in the search.
(Google does 1 & 2, as do many others, included a video of expected behavior)
I suspect #2 is by far the easiest to implement, so I'd consider doing #2 as a fix and then considering #1 or #3 as a future feature. 
