The four groups
Vim modes
NORMAL · INSERT · VISUAL · REPLACE
JavaScript KeyboardEvent.key values
ENTER · SHIFT · BACKSPACE · TAB
Default VSCode bottom-panel tabs
PROBLEMS · OUTPUT · TERMINAL · DEBUG
Words paired with ROOM
BED · CONTROL · NEWS · ELBOW
Why this puzzle works
Difficulty-5. Three different concept categories collide on overlapping intuitions: CONTROL screams 'Ctrl key' (KeyboardEvent has 'Control'!) but it's purple (control room). REPLACE is a vim mode *and* a VSCode action, but the cardinality forces it into yellow. TERMINAL could mean the unix shell or the VSCode panel — here it's the panel. The trick to devious puzzles is to find the *least-overlapping* tile first (NEWS, ELBOW for purple; PROBLEMS for VSCode) and let those constrain the rest.
How to read a Connectle without solving it
A code-themed grouping puzzle rewards counting as much as recognition. Start by listing every plausible group, then notice which tiles appear in two lists. Whichever group has exactly four unambiguous members is your anchor — solve it first and the rest of the board collapses by elimination. The hardest tier (purple) is almost always wordplay: tiles that share a prefix or suffix, not a concept. If a tile feels orphaned, ask whether the same word could follow or precede a common engineering word like root, stack, cache, or queue.