Undesired merging "fi" into one glyph

[Fluorspar93]

When a lowercase "f" is followed by a lowercase "i", it seems they automatically stick together as a single glyph "fi", in the sense that these two letters together occupy the space for only one character instead of two. I have observed this in both gedit and TeXStudio. Is it possible to disable this feature so that f and i each occupy the space for one character (for a total of two characters together)? I considered that this might be an application issue, but I have only observed this with Kawkab Mono and not with any other monospace fonts in the same applications. Thank you.