TYPE_PRIORITY, TYPE_RST_STREAM, TYPE_GOAWAY, TYPE_WINDOW_UPDATE -> return BINARY[flags]
    }
    val result = if (flags < FLAGS.size) FLAGS[flags]!! else BINARY[flags]
    // Special case types that have overlap flag values.
    return when {
      type == TYPE_PUSH_PROMISE && flags and FLAG_END_PUSH_PROMISE != 0 -> {
        result.replace("HEADERS", "PUSH_PROMISE") // TODO: Avoid allocation.
      }

 *
 * Mappings Data (4,719 bytes)
 * ===========================
 *
 * This is UTF-8 character data. It is indexed into by b2b3 in the ranges dataset.
 *
 * Mappings may overlap.
 *
 * ASCII-Only
 * ==========
 *
 * Neither the section index nor the ranges data use bit 0x80 anywhere. That means the data is

Where the spec is ambiguous, OkHttp follows modern user agents such as popular Browsers or common HTTP Libraries.

OkHttp is principled and avoids being overly configurable, especially when such configuration is
to workaround a buggy server, test invalid scenarios or that contradict the relevant RFC.