Minecraft 1.12.2 is one of the older versions with a large mod library and long-existing projects. The selection is generated automatically according to the version that the server publishes in the status protocol.
Yeah. Some projects continue to use this version because of their own modpaks, mechanics or accumulated content.
Normally not without special compatibility tools. Check the stated version range of a particular server.
#brsc-root{position:fixed;right:22px;bottom:22px;z-index:2147481000;font:14px/1.45 system-ui,-apple-system,'Segoe UI',Arial,sans-serif;color:#e9f2fc;text-align:left;box-sizing:border-box} #brsc-root *{box-sizing:border-box} #brsc-root button,#brsc-root textarea{font:inherit;box-sizing:border-box} #brsc-open{display:flex;align-items:center;gap:9px;width:auto;min-height:52px;border:1px solid #578cf2;border-radius:999px;padding:12px 18px;background:linear-gradient(135deg,#2170e4,#1247aa);color:white;box-shadow:0 9px 28px rgba(0,27,84,.3);cursor:pointer;font-weight:750} #brsc-open:hover{filter:brightness(1.13)} #brsc-root svg{width:21px;height:21px;flex-shrink:0;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round} #brsc-panel{display:none;width:min(370px,calc(100vw - 26px));height:min(535px,calc(100dvh - 100px));min-height:280px;border-radius:17px;overflow:hidden;background:#111b2b;box-shadow:0 18px 65px rgba(0,0,0,.43);border:1px solid #3a526e;flex-direction:column} #brsc-root.brsc-active #brsc-panel{display:flex} #brsc-root.brsc-active #brsc-open{display:none} #brsc-head{padding:17px 18px;background:linear-gradient(120deg,#1d5099,#162e53);color:#fff;display:flex;justify-content:Space-between;align-items:center;gap:12px} #brsc-head b{display:block;font-size:16px;line-height:1.2} #brsc-head small{display:block;font-size:11px;color:#d4e5fb;margin-top:3px} #brsc-close{width:32px;height:32px;border:1px solid rgba(255,255,255,.25);border-radius:8px;padding:5px;background:rgba(255,255,255,.08);color:#fff;cursor:pointer} #brsc-chat{flex:1;min-height:0;overflow-y:auto;padding:16px;display:flex;flex-direction:column;gap:10px;background:linear-gradient(#101925,#131e2d);overscroll-behavior:contain} .brsc-bubble{max-width:89%;padding:10px 12px;border:1px solid #34435b;border-radius:13px 13px 13px 3px;overflow-wrap:anywhere;white-Space:pre-wrap;background:#202e42;color:#edf4fd} .brsc-bubble.brsc-visitor{align-self:flex-end;border-color:#3066a3;border-radius:13px 13px 3px 13px;background:#194780;color:#fff} .brsc-bubble.brsc-support{align-self:flex-start} .brsc-time{display:block;font-size:10px;opacity:.7;margin-top:5px;text-align:right} #brsc-empty{text-align:center;align-self:center;color:#bdcce0;font-size:13px;max-width:250px;margin:auto} #brsc-status{min-height:17px;padding:3px 15px;font-size:11px;color:#a9bfd9;background:#111b2b} #brsc-form{margin:0;padding:10px 12px 7px;background:#111b2b;border-top:1px solid #314359;display:flex;gap:7px;align-items:flex-end} #brsc-input{flex:1;min-width:0;width:auto;max-height:116px;min-height:43px;resize:vertical;padding:10px 11px;background:#1c2a3a;color:#fff;border:1px solid #46617d;border-radius:10px;outline:none;line-height:1.35} #brsc-input:focus{border-color:#7aa9ff} #brsc-send{width:auto;min-width:75px;height:43px;padding:9px 11px;border-radius:10px;background:#256fe3;border:1px solid #428aff;color:#fff;font-weight:700;cursor:pointer} #brsc-send:disabled{opacity:.45;cursor:default} #brsc-privacy{padding:0 13px 10px;font-size:10px;color:#9eafc4;background:#111b2b} #brsc-privacy a{color:#aed2ff;text-decoration:underline} /* Keep the closed launcher above the decorative right-side character on wide screens. */ @media(min-width:1500px) and (min-height:620px){#brsc-root:not(.brsc-active){bottom:190px}} @media(max-width:530px){#brsc-root{right:12px;bottom:12px}#brsc-open{padding:12px 14px;min-height:49px}#brsc-panel{height:min(555px,calc(100dvh - 24px));width:calc(100vw - 24px)}} @media(prefers-reduced-motion:reduce){#brsc-open{transition:none}}
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