The proposed solutions (What should have happened instead?) are covered by T343767: Enforce the short description length limit in the API on saving and T343768: Term input fields should have maxlength set, but this task may continue to be open for UI issues (e.g. if we add 100 a's as alias).

In T360510#9645193, @Bugreporter wrote:

The proposed solutions (What should have happened instead?) are covered by T343767: Enforce the short description length limit in the API on saving and T343768: Term input fields should have maxlength set, but this task may continue to be open for UI issues (e.g. if we add 100 a's as alias).

(strictly, these two tasks does not fully cover the proposed solution. e.g. If you edit an older revision, it may contain overlong terms, which will be - though currently is not - invalid, and the original proposed solution proposed to prevent publish it. However, even if user can publish it, it will be disallow by server-side checking once enforced. Therefore checking term length server-side is a requirement to enforce term length limit, checking it client side is not a requirement; once we also set maxlength in input field, additional client-side checking will only catch niche cases including editing of older revisions, which will also be disallowed in server-side check anyways.)

I think this just needs something like:

// (T360510) Sometimes user-written content is long and otherwiseunbroken.
.ext-wikilambda-about-value {
	overflow-wrap: break-word;
}

… added somewhere in About.vue?

Change #1043162 had a related patch set uploaded (by Ecarg; author: Ecarg):

[mediawiki/extensions/WikiLambda@master] Fix word overflow issue in About.vue description widget

https://gerrit.wikimedia.org/r/1043162

Change #1043162 merged by jenkins-bot:

[mediawiki/extensions/WikiLambda@master] Fix word overflow issue in About.vue description widget

https://gerrit.wikimedia.org/r/1043162