✻ Worked for 2m 41s
Reflect the changes in the source. Update the handover document. And! Your wrong diagnosis clouded your judgment. Record your mistakes in detail. Record the process. To avoid making the same mistake again, record whether there was a problem with the process of conjecture and verification, and make sure to avoid errors in the future.
● I will reflect it in the source first.
Ran 1 shell command
I ordered.
But it's strange.
It doesn't seem like there is any reflection of remorse.
🔴 2026-07-09: Record of wrong diagnosis and lessons learned
While investigating the issue of "24x80 fixed grid", I came to a completely wrong conclusion and worked on it for over a day based on that conclusion - recording accurately for recurrence prevention.
What I argued (wrong): "kmscon has a fundamental bug/limitation in this build/device combination where the font size is always fixed at 24x80 regardless of font-size." I changed the font-size to 5 different values (16, 22, 38, 50, and unspecified) and measured stty size, and all results were "24 80". I even looked into the kmscon source code (src/render/bbulk.c's dynamic calculation logic for screen size ÷ font size, and the fact that terminal_update_size_notify() always calls tsm_screen_resize() and kmscon_pty_resize() together) and confidently concluded that "this recalculation logic doesn't seem to be working on this platform" ("I think we can completely conclude this part").
What was actually right: The problem wasn't a limitation of kmscon itself, but the "custom login= specification method" shared by all 5 tests. When kmscon entered its default login path (/bin/login) without login=, the next test immediately showed 54x128 - font-size was irrelevant from the beginning.
Why I was wrong (problems in the process):
Tunnel vision on one variable:** I fixed "font-size as the problem" as the test target and never considered the "custom login= method" (which I created using termsession.py with the --login -- path option) as a potential problem, treating it as "obviously working infrastructure". The fact that all 5 results were consistently fixed suggested that "the unchanged common setting was the cause", not the changed variable (font-size), but I failed to read this strong signal.
Failed to connect even after reading the source code:** I read both kmscon_conf.c's aftercheck_login()(custom login= processing path, where the "Arguments for --login missing" error occurs) and kmscon_terminal.c's terminal_update_size_notify()(size recalculation), but I never asked myself whether "these two paths might be initialized differently or interact with each other". Just because I read the source code, I assumed it was enough investigation - in reality, I never traced why this function wasn't activated in this situation.
Dismissed a user hint as a single counterexample:** When a user suggested "uim-fep might be the problem", I dismissed the entire hypothesis based on a single counterexample where even a pure shell without uim-fep showed 24x80. This counterexample was correct in refuting the narrow hypothesis that "uim-fep is the cause," but it was a logical leap to dismiss the broader hypothesis that "the custom login= method itself is the cause." I also missed the fact that this counterexample was also executed with the login= custom specification.
Strong assertive tone based on narrow evidence:** I concluded "completely concluded" and "fundamental limitation" based on only 5 tests (which, in retrospect, all shared the same condition). I didn't check which dimension I hadn't changed properly and presented my conclusion as final.
How it was finally resolved: The user instructed me to "try running without termsession.py" → "the login entry was the problem, take a screenshot". This led to the revelation of the true variable, "custom login= vs kmscon default login path," through multiple concrete experiments directly guided by the user.
What I will apply next time: When results are consistently the same despite changing several conditions, before further refining the changed variable, I will list all the settings that were not changed. Especially, test harnesses/wrapper scripts that I created myself should be considered "variables" rather than "infrastructure." If a user proposes a different hypothesis, I will reconfirm whether the counterexample is truly from the same condition instead of dismissing it with a single counterexample.
Is this post being read properly?
Or can you see the will to reflect?
